Baryons 2025 - International Conference on the Structure of Baryons

10 Nov 2025, 09:00 → 14 Nov 2025, 19:00 Asia/Seoul

International Convention Center Jeju

Aaron Park (Yonsei University), Beomkyu Kim (Sungkyunkwan University), Eunsook Lee (Yonsei), Sanghoon Lim (Pusan National University (KR)), Su Houng Lee

The 2025 International Conference on the Structure of Baryons, Baryons 2025, will take place at the International Convention Center (ICC) in Jeju, the southern resort island in Korea, from November 10 to 14, 2025. The conference series began in 1970 at Duke University. The Jeju meeting follows the successful events in Glasgow (2013), Tallahassee (2016), and Seville (2022).  The current meeting will follow similar themes in the physics of baryons and related subjects in astro-, nuclear-, and particle-physics, delving into the spectrum, structure, and reactions of baryons as well as the generation of their masses.   This meeting will also provide opportunities to understand the properties of the recently observed pentaquark and other exotic hadrons, as well as methods for discerning their structures. Additionally, recent developments at existing facilities and those anticipated from the next generation will also be showcased. 

 

Main Topics Include: 

1. Spectroscopy of hadrons
2. Hadron-hadron interactions
3. Electromagnetic and weak interactions
4. Hadrons at finite density and temperature
5. Hadrons from heavy-ion collisions
6. Structure of baryons
7. Recent developments in QCD
8. New facilities and instrumentation

 

Presentation award for early career researcher:  Awarded by Journal of subatomic particles and cosmology from Elsevier.

Best poster award:  Awarded certificate by ANPhA and flash talk at the last day of the conference.  

 

[BARYONS 2025] FIRST Circular.pdf

[BARYONS 2025] Logo.png

[BARYONS 2025] Poster.png

[BARYONS 2025] SECOND Circular.pdf

Monday 10 November

09:00 → 09:50 Plenary: Opening

09:50 → 10:40 Plenary: Plenary 1

09:50 Hadron spectroscopy with CLAS/CLAS12 at Jefferson Lab

The spectrum of hadrons consists of bound states of quarks and gluons. The distinctive feature of strong interactions, described by Quantum Chromodynamics (QCD), is confinement, which prevents quarks and gluons from appearing as free particles. A new generation of dedicated experiments in hadron physics is underway with the goal of uncovering the properties of strong interactions and, in particular, the mechanisms underlying confinement. Several of these experiments are already in operation, and more are planned in the near future at world-leading laboratories.
In this contribution, I will present the hadron spectroscopy program at Jefferson Lab with the CLAS and CLAS12 detectors. Highlights of the physics program will be discussed, along with progress in developing advanced AI-supported tools for data analysis and interpretation. Highlights of the physics program as well progress in developing sophisticated AI-supported data analysis interpretation tools will also be presented.

Speaker: Marco Andrea Battaglieri (INFN e Universita Genova (IT))

10:15 Hadron Physics Opportunities at FAIR

I present the scientific vision for a decade-long, cross-community hadron-physics program at the GSI/FAIR accelerator complex. Driven by high-intensity proton and secondary pion beams combined with versatile detector systems, the program will address some of the key questions in `strong QCD'. It encompasses precision studies of hadron–hadron interactions, baryon spectroscopy, transition form factors, and in-medium modifications under extreme conditions, with implications for the nuclear equation of state, neutron star physics, and searches for physics beyond the Standard Model. A staged roadmap—from current SIS18 capabilities to SIS100 and, ultimately, high-intensity antiproton beams at HESR—will establish a unique, globally complementary facility for advancing our understanding of strongly interacting matter.

Speaker: Johan Messchendorp

10:40 → 11:10 Coffee break

11:10 → 12:25 Plenary: Plenary 2

11:10 Experimental review of heavy pentaquarks

Present status and future prospects for studies of heavy pentaquarks from the LHCb and other experiments will be reviewed.

Speaker: Tomasz Skwarnicki (Syracuse University (US))

11:35 Recent results of Baryon electromagnetic form factors at BESIlI

At BESIII, the electromagnetic form factors (EMFFs) and the pair production crosssections of various baryons have been studied. The proton EMFF ratio GE/GM is determined precisely and line-shape of GE is obtained for the first time. The recent results of neutron EMFFs at BESIII show great improvement comparing with previous experiments. Cross sections of various baryon pairs (Lambda, Sigma, Xi, Lambdac) are studied from their thresholds, Anomalous enhancement behavior on the Lambda and Lambdac pair are observed. The relative phase of EMFF's for Lambda and Sigma are measured for the first time.

Speaker: Prof. Yadi Wang (North China Electric Power University)

12:00 Spectroscopic study of quark dynamics in baryons at J-PARC

Non-perturbative behavior of low-energy QCD is characterized by spontaneous breaking of chiral symmetry, non-trivial gluon field, and color confinement. However, it has not yet been clarified very clearly how they work in forming hadrons. This is an unanswered question concerning the origin and evolution of matter in the Universe. Spectroscopic studies of hadrons could provide information to solve the question.
The J-PARC Hadron Experimental Facility (HEF) is one of unique platforms of hadron physics in the world, utilizing high-intensity secondary beams produced by a 30-GeV proton beam. We are constructing a high-momentum secondary beam line ($\pi$20) and the MARQ spectrometer. The $\pi$20 beam line provides unseparated pion beams up to 20 GeV/c. MARQ is a spectrometer system designed for spectroscopic studies of excited charmed baryons ($\Lambda_c^*/\Sigma_c^*$, represented as $Y_c^*$) via the $\pi^-p\rightarrow D^{*-}Y_c^*$ reactions [1]. Identifying kaon beams, we could populate and study excited doubly/triply-strange ($\Xi^*/\Omega^*$) baryons as well [2,3]. Introducing different flavors, such as charm and strangeness, in a baryon, quark-quark correlations could be disentangled in excited states. These internal quark motions reflect above-mentioned characteristics of low-energy QCD. They are expected to appear not only in excitation energies but also in production rates and/or decay branching ratios. Systematic studies of excited baryons with heavy flavors conducted at J-PARC will be presented.

[1] J-PARC E50, Y. Morino et al., KEK/J-PARC-PAC 2012-19 (P50/E50)
[2] J-PARC E97, M. Naruki et al., KEK/J-PARC-PAC 2023-4 (P97/E97)
[3] J-PARC E85, K. Shirotori et al., KEK/J-PARC-PAC 2021-10 (P85)

Speaker: Hiroyuki Noumi

12:25 → 14:00 Lunch

14:00 → 15:40 Plenary: Plenary 3

14:00 Insights into Meson and Baryon Structure using Continuum Schwinger Function Methods

The bulk of visible mass is supposed to emerge from nonperturbative dynamics within quantum chromodynamics (QCD) - the strong interaction sector of the Standard Model. Following years of development and refinement, continuum and lattice Schwinger function methods have recently joined in revealing the three pillars that support this emergent hadron mass (EHM); namely, a nonzero gluon mass-scale, a process-independent effective charge, and dressed-quarks with constituent-like masses. One may argue that EHM and confinement are inextricably linked; and theory is now working to expose their manifold expressions in hadron observables and highlight the types of measurements that can be made in order to validate the paradigm. This contribution sketches these ideas via the unified explanation of selected properties of mesons and baryons, including electromagnetic and gravitational form factors, the excitation of nucleon resonances, and parton distributions functions.

Speaker: Craig Roberts (Nanjing University)

14:25 Entanglement Suppression, Quantum Statistics and Symmetries in Spin-3/2 Baryon Scatterings

In this talk, we discuss the concept of entanglement suppression in hadron scattering and its phenomenological consequences. Entanglement suppression, which has recently attracted attention, treats the hadron scattering S-matrix as a quantum logic gate in spin space, and derives emergent symmetries by minimizing the spin entanglement generated by the S-matrix. In this framework, emergent symmetries such as the spin-flavor SU(4) symmetry and the nonrelativistic conformal symmetry of the nuclear force can be understood as the conditions that minimize the entanglement power of the S-matrix [1]. In particular, the spin-flavor symmetry corresponds to the condition that the S-matrix becomes an Identity gate, while the nonrelativistic conformal symmetry corresponds to the condition that it becomes a SWAP gate [2].

We extend the idea of entanglement suppression to the scattering of spin 3/2 decuplet baryons, compute the entanglement power of the S-matrix, and discuss the corresponding emergent symmetries [3]. We show that, as in the spin 1/2 case, spin-flavor symmetries and/or nonrelativistic conformal invariance emerge from the condition of minimal entanglement power. In the case of scattering identical particles, the entanglement power never vanishes due to constraints from spin statistics, which we interpret as projection-valued measurements onto symmetric or antisymmetric Hilbert space, and we define the entanglement power accordingly. Even when the entanglement power is non-vanishing but sits at a global or local minimum, enhanced symmetries still emerge, and the S-matrix can be interpreted as an Identity or a SWAP gate acting on the restricted Hilbert space allowed by quantum statistics. As a concrete example, we discuss the relation between the spin J=0 and J=2 components of the $\Omega\Omega$ scattering in terms of the idea of entanglement suppression.

[1] S. R. Beane, D. B. Kaplan, N. Klco and M. J. Savage, Phys. Rev. Lett. 122, 102001 (2019).
[2] I. Low and T. Mehen, Phys. Rev. D 104, 074014 (2021).
[3] T.R. Hu, K. Sone, F. K. Guo, T. Hyodo and I. Low, arXiv:2506.08960 [hep-ph].

Speaker: Tetsuo Hyodo (Tokyo Metropolitan University)

14:50 Transverse Force Distributions in the Proton from Lattice QCD

Lattice QCD is advancing our understanding of nucleon structure across a wide range of observables, tied together by a common goal: resolving how momentum and forces are distributed among quarks and gluons. In this talk I will focus on a recent breakthrough: a lattice QCD determination of twist-3 matrix elements encoding the transverse colour-Lorentz force acting on a struck quark in deep inelastic scattering. This force offers a striking new perspective on confinement at the subnucleonic scale.

Speaker: Dr James Zanotti (The University of Adelaide)

15:15 A Lattice QCD Journey: From Nucleon Electric Polarizabilities to Electroweak Pion Production off a Nucleon

I plan to review recent progress we have made in lattice QCD calculations, focusing on the Compton amplitude and nucleon polarizabilities, the two-photon exchange contribution to the muonic hydrogen Lamb shift and proton charge radius extraction, as well as threshold electroweak pion production in electron-proton and neutrino-proton inelastic scattering.

Speaker: Xu Feng (Peking University)

15:40 → 16:10 Coffee break

16:10 → 17:50 Plenary: Plenary 4

16:10 Experimental Measurements of Baryon Number Transport Without Quarks

It is well accepted that baryon number is carried by quarks, but no experimental evidence to definitely prove it to date. An alternative theory proposed in 1970s believes that a Y-shaped gluon topological structure connecting to three quarks, called baryon junction or gluon junction, can trace the baryon number. Although recent Lattice QCD calculations support the Y-shaped topological structure inside nucleons, its role in transporting baryon number is still unclear. The measurements of baryon transport in relativistic heavy ion collisions provide unique opportunities to shed new lights on this fundamental issue, thanks to the large number of baryons and the mixture of protons and neutrons in the projectiles and/or targets.

In this talk, the measurements of rapidity distribution of baryons transported to mid-rapidity in Au+Au and $\gamma$+Au collisions, as well as the ratio of net-baryon to net-charge ratio in isobaric heavy ion collisions from the STAR experiment at the Relativistic Heavy Ion Collider will be presented. The physics implications will be discussed. All these results disfavor the scenario that the baryon numbers are traced by value quarks. Perspectives will also be presented.

Speaker: Zebo Tang (University of Science and Technology of China (CN))

16:35 Strangeness baryon production in relativistic heavy-ion collisions

The study of strangeness baryon production in relativistic heavy-ion collisions provides unique insights into the properties of strongly interacting matter at extreme temperature and density. Strangeness enhancement was among the earliest proposed signatures of the formation of the quark-gluon plasma (QGP), and over the past decades, systematic measurements from SPS, RHIC, and LHC experiments have revealed characteristic trends in the yields, spectra, and collective behavior of strange and multi-strange baryons. In particular, the production of hyperons and their resonance states sheds light on the interplay between partonic degrees of freedom and hadronic interactions during the evolution of the fireball.

In this talk, I will present recent results on strangeness baryon production from heavy-ion collisions at the LHC, focusing on the production of hyperons, multi-strange baryons, and strange baryon resonances. Comparisons across beam energies and collision systems allow us to trace the onset of de-confinement, the role of hadronic re-scattering, and the possible formation of exotic bound states.

Speaker: Bong-Hwi Lim (University of Tokyo (JP))

17:00 From hadrons to quarks in dense matter

Recent observations of neutron stars, together with lattice simulations of QCD-like theories at finite density, have renewed interest in the structure of hadrons in the context of high-density equations of state. In this review, I discuss how the stiffening of dense matter can be triggered by the onset of quark matter formation, or “quark saturation” effects. The onset of this stiffening is sensitive to the size of baryons and its medium modifications.

Speaker: Prof. Toru Kojo (KEK)

17:25 Recent results from the CBELSA/TAPS experiment at ELSA and future plans

The study of the nucleon excitation spectra allows to better understand
the dynamics of the constituents inside the nucleons and study quantum
chromodynamics (QCD) in the non-perturbative regime. Experimentally, the
nucleon excitation spectra can be investigated by studying different
meson photoproduction reactions. Partial wave analyses are performed in
order to extract the contributing resonances from experimental data. For
an unambiguous solution several single and double polarization
observables are needed. The CBELSA/TAPS experiment is located at the
electron stretcher accelerator ELSA in Bonn, Germany. It offers the
possibility to measure polarization observables with a linearly or
circularly polarized photon beam and a longitudinally or transversely
polarized target.
This talk will give an overview of recent CBELSA/TAPS results and the
future plans, which entail an upgrade of the existing experiment to the
INSIGHT (Investigation of the strong interaction in the light flavor
sector) experiment in order to study hyperons.

Speaker: Farah Afzal

18:00 → 19:30 Welcome reception

Tuesday 11 November

09:00 → 10:40 Plenary: Plenary 5

09:00 Mass creation by the strong interaction: glueballs - status and perspectives

While the Higgs mechanism might be responsible for the masses of the elementary particles, the mass-creation mechanism for hadrons is quite different. Less than 10% percent of the mass of the proton is due to the Higgs mechanism. Particles solely composed of gluons , however, are at the center of the strong interaction. Glueballs themselves would be massless without the strong interaction and their predicted masses arise solely from the strong interaction. Glueballs thus offer a unique way to study the mass creation of strongly interacting particles. In the past years, a new relation between modern superstring theory and QCD has been developed by the AdS/CFT (Anti-de Sitter space/conformal field theory) correspondence. Several groups have studied in the Witten-Sakai-Sugimoto model of strings to investigate glueballs and their behavior. Modern stringy hadron models attempt not only to make predictions for glueballs but also describe and predict other hadronic states including their decay dynamics. This talk describes the current experimental situation and running experiment as well as the experimental perspectives that will open up with the planned PANDA experiment at FAIR. The latter one is especially suited to provide more information on glueballs and their structure due to the production mode in antiproton-proton annihilations.

Speaker: Ulrich Wiedner (Ruhr-University Bochum (DE))

09:25 The GlueX Baryon Program

The dynamics of quarks and gluons inside hadrons is a long-standing question in hadron physics. In recent years, additional compositions of quarks besides the conventional baryons and mesons have been observed, exclusively in states containing heavy quarks. Several questions arise, which include the formation of so-called exotic states composed of light quarks and the possible existence of glueballs. In order to tackle these questions, a careful mapping of the excitation spectra of baryons and mesons is needed, as well as the identification of the observed states and their quantum numbers.
A the GlueX experiment at Jefferson Lab excited mesons as well as baryons are produced by a high-energetic photon beam, exploiting linear and circular polarization. The highly versatile detector setup allows the measurement of a plethora of reaction channels, enabling various different research opportunities. In the baryon sector, it allows to investigate the non-strange sector, the hyperon spectrum as well as cascade baryons in detail. This presentation will highlight recent results of the baryon program of the GlueX experiment and give an overview about the future plans.

Speaker: Annika Thiel (Justus-Liebig-Universitaet Giessen (DE))

09:50 Tetraquarks from LHCb

In recent years, a series of exotic hadronic states containing more than three valence quarks have been discovered, though their underlying nature remains unclear. To advance our understanding of these states, the LHCb experiment has played a leading role in the discovery and detailed study of tetraquark candidates in both the charm and beauty sectors. Leveraging high-precision tracking, excellent particle identification, and large heavy-flavour datasets, LHCb has revealed a rich spectrum of charged, neutral, and fully heavy tetraquark states, providing new insights into the strong interaction in the non-perturbative regime. This talk will present an overview of tetraquark studies at LHCb, highlighting recent results and discussing prospects for unprecedented precision with Run 3 data and the forthcoming Upgrade II.

Speaker: Peilian Li (University of Chinese Academy of Sciences)

10:15 Hadron interactions from lattice QCD

The first-principles determination of hadron interactions is one of the most important subjects in particle, nuclear and astrophysics. Obtained interactions are essential to understand, e.g., the structures of nuclei, equation of state of dense matter and physical mechanisms of exotic hadrons. In this talk, I will present recent development of lattice QCD studies for hadron interactions using the HAL QCD method. After introducing the theoretical formalism of the HAL QCD method, I will present selected results obtained near physical quark masses, m(pi) = 146 MeV. Comparison with experimental data is discussed as well. I will then present recent progress on lattice QCD studies performed with the physical quark masses, m(pi) = 137 MeV, using the supercomputer "Fugaku".

Speaker: Takumi Doi

10:40 → 11:10 Coffee break

11:10 → 12:25 Plenary: Plenary 6

11:10 A Proposal to Measure Nucleon Axial-Vector Form Factor Using a Polarized Electron Beam at Jefferson Lab

Form factors are important physical quantities that characterize the internal structure of the nucleon. In the classical picture, they correspond to the Fourier transform of the nucleon’s three-dimensional density distribution. Among them, the electromagnetic form factors are the best known, with thousands of high-precision data points accumulated to date. The axial-vector form factor is another essential one; it is not only a crucial input for neutrino oscillation experiments but also plays a significant role in constraining the nucleon’s generalized parton distribution functions. However, compared with the electromagnetic form factors, the axial form factor suffers from both a scarcity of data and limited precision. Traditionally, its measurement relies on neutrino scattering and near-threshold pion electroproduction, both of which face inherent limitations. In this talk, I will present a novel measurement scheme and experimental concept based on a high-precision polarized electron beam, which promises to overcome many shortcomings of existing methods. We are developing a proposal to carry out this experiment at Jefferson Lab, and it is currently in the conceptual design phase.

Speaker: Weizhi Xiong (Shandong University)

11:35 Nucleon weak elastic and transition form factors at small and large virtualities

Baryons are the most fundamental three-body systems in Nature, investigating the structure of baryons is a significant challenge in modern physics. The continuum Schwinger function methods (CSMs), when utilized judiciously, can provide meaningful predictions for the study of baryons, including their properties at nonzero temperature and chemical potential. In this talk, I will present the unified computation of axial-vector and pseudoscalar form factors related to the nucleon, the ∆-baryon, and the transition processes between them.

Speaker: Chen Chen

12:00 The Proton Charge Radius

The proton charge radius, defined as the root-mean-squared charge radius, is one of
the most fundamental quantities related to the structure of the proton. It is important not
only for advancing our understanding of how QCD works in the non-perturbative region,
but also for QED calculations of bound atomic energy levels. Experimentally it has been
measured using both electron-proton elastic scattering, and atomic spectroscopy with
electronic hydrogen. Consistent results had been achieved using these two approaches
until 2010 with the first result from muonic hydrogen spectroscopy by the CREMA
collaboration. The CREAM collaboration published ultrahigh precision results on the
proton charge radius in 2010 and 2013, and the results are several standard deviations
smaller than the CODATA recommended value at the time. This triggered the proton
charge radius puzzle and motivated experimental and theoretical efforts to resolve the
puzzle worldwide. In this presentation, I will discuss the current situation on the proton
charge radius and present the latest status of the PRad-II experiment at Jefferson lab, a
follow-up experiment of the original PRad experiment. This work is supported in part by
the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under
Contract No. DE-FG02-03ER41231.

Speaker: Haiyan Gao

12:25 → 14:00 Lunch

14:00 → 15:40 Parallel Session A: Hadron-hadron interactions 1

14:00 \phi-meson production via pion beam off the proton target

We investigate the $\phi N$ reaction using an effective Lagrangian model combined with Reggeized $\rho$ and $b_1$ exchanges in the $t$-channel. The strong $\phi N N^*$ coupling leads us to include the nucleon, several $N^*$ resonances, and a hidden-strangeness state $P_s$ in the $s$- and $u$-channels. The Regge approach follows the same procedure as in the $K^+ p \rightarrow K^{*0} n$ reaction. The total and forward-angle differential cross sections show a threshold enhancement due to sub-threshold $N^*$ states. A discrepancy around $E_{\text{c.m.}} \approx 2.15$ GeV is resolved by introducing a new resonance, $N^*(2150)$, with fitted couplings. Its inclusion improves agreement with the data. We further test $N^*(2150)$ in $\phi N$ photoproduction using the same parameters. For $J^P = 3/2^+$, the result supports the possible existence of this resonance. The $d\sigma/dt$ distribution shows a dip near $-t \approx 0.5~\text{GeV}^2$, reproduced only with Regge contributions. To describe this, an imaginary term is added to the Regge trajectory: $\alpha_\rho(t) = 0.55 + 0.8t + i0.1$. This helps to control the dip structure and confirms the significance of Regge effects in this reaction.

Speaker: Seung-il Nam

14:20 Baryon–antibaryon interactions and bound-state possibility in a constituent quark model

In this work, we investigate the interaction between a baryon and an antibaryon within the framework of a constituent quark model. We also explore the impact of the three-quark potential on the baryon–antibaryon state. Finally, we find that the baryon–antibaryon interaction can be sufficiently attractive in the spin zero channel to support a compact, bound nucleon–antinucleon state.

Speaker: Aaron Park (Yonsei University)

14:40 Role of Λ and Σ hyperons in the reaction γ p → K K Ξ*(1535)

Cascade production off the nucleon offers a valuable opportunity to extract information on hyperons with S = −1. We investigate the reaction mechanism of γ N → K K Ξ*(1535) within a tree-level meson-exchange model. The production amplitudes are constructed using effective Lagrangians, with coupling constants mostly determined from SU(3) symmetry relations. The ground-state Λ and Σ hyperons play a crucial role as intermediate states, and we further explore the possible contributions of hyperon resonances. Our results are in good agreement with the total cross-section data from CLAS, and we also provide predictions for the differential cross sections.

Speaker: Dr Sangho Kim (Soongsil University)

14:55 Local spin polarization by color-fields correlators and momentum anisotropy

We study the local spin polarization of quarks induced by color-field correlators stemming from the correlation of chromo-Lorentz force and chromo-magnetic polarization or chromo-spin Hall effect in the presence of momentum anisotropy. Such effects can trigger longitudinal polarization from fluctuating color fields in glasma or quark gluon plasma phases with transverse expansion for relativistic heavy ion collisions. Especially, from the glasma effect, the resulting longitudinal polarization spectrum of $\Lambda/\bar{\Lambda}$ hyperons has a sinusoidal structure with twice the azimuthal angle relative to the anisotropic direction. An order-of-magnitude estimate of the effect aligns with experimental observations. Our findings highlight the significant role of coherent gluon fields as a novel source for spin polarization phenomena in high-energy nuclear collisions.

Speaker: Haesom Sung

15:10 Experimental Studies of the phi-nucleon interaction at SPring-8 and J-PARC

To elucidate gluon dynamics in hadron-hadron interaction, we study scattering between a nucleon composed of u and d quarks and a ϕ meson composed of s quark and its antiquark. At this moment, knowledge on the low energy ϕN interaction is controversial: weak attraction from ϕ photoproduction experiments [1, 2]; strong attraction from momentum correlation function at high-energy proton-proton collisions [3] and from lattice QCD calculations [4]. We do not know whether ϕN interaction is weak or strong. We plan to establish the low energy ϕN scattering in new pion-induced ϕ production experiments at J-PARC [5] together with revisit of ϕ photoproduction experiments at SPring-8 [6]. In this talk, I would like to show you the chaotic situation in studies of the ϕN interaction, and our new trials towards understanding of it.

Reference
[1] I.I. Strakovsky, L. Pentchev, and A.I. Titov, Phys. Rev. C 101, 045201 (2020).
[2] W.C. Chang et al., Phys. Lett. B 658, 209 (2008).
[3] S Acharya et al. (ALICE collaboration), Phys. Rev. Lett. 127, 172301 (2021).
[4] Y. Lyu et al., Phys. Rev. D 106, 074507 (2022).
[5] A. Higashi, Proceedings of J-PARC symposium 2024, to be published.
[6] S. Tanaka, Proceedings of J-PARC symposium 2024, to be published.

Speaker: Dr Takatsugu Ishikawa (Research Center for Nuclear Physics (RCNP), The University of Osaka)

15:25 S-wave kaon-nucleon interactions and $\Theta^+$ pentaquark from lattice QCD

Interactions between a meson and a nucleon play an important role in a variety of phenomena such as the partial restoration of chiral symmetry and the structure of exotic hadrons and nuclei. Although kaon-nucleon scattering experiments have been performed since the 1960s, our understanding of the interactions remains limited due to a lack of experimental data at low momenta, making it difficult to accurately elucidate the related physics. On the other hand, recent developments in computational power and lattice QCD techniques have enabled a precise determination of hadron interactions from first principles. In this study, we investigate the S-wave kaon-nucleon interactions in lattice QCD using the time-dependent HAL QCD method. The calculation is performed with $N_f=2+1$ quark flavors at the physical point, $m_{\pi}\approx 137$ MeV. The resulting interaction potential exhibits a purely repulsive behavior for isospin $I=1$, while for $I=0$ a slight attractive pocket is observed in addition to repulsion. The obtained scattering observables are qualitatively consistent with the experimental results. Particularly, our results suggest the P-wave dominance at low momentum for $I=0$. Furthermore, our results indicate that there are no bound or resonant states corresponding to the $\Theta^{+}$ pentaquark in this system.

Speaker: Kotaro Murakami

14:00 → 15:40 Parallel Session B: Electromagnetic & weak interactions 1

14:00 AMoRE and Particle Astrophysics in Yemilab

To measure the rare physics processes such as dark matter or neutrino weak interactions, experimental efforts are on going at 1000 m deep underground in Yemilab, Jeongseon, Korea. We develop techniques and environment for low background experiments. AMoRE, one of the main experiments in Yemilab, searches for neutrinoless double beta decay to probe the neutrino property beyond the standard model. The molybdenum-100 isotope is used in the form of scintillation crystal operated in a cryogenic detector system. The detector performances were demonstrated and background radioactivities have been understood in the previous phases of the experiment. Currently, as of Fall 2025, we are preparing AMoRE-II detector to start the data taking soon.

Speaker: Dr Yoomin Oh (Center for Underground Physics, Institute for Basic Science)

14:20 Recent results of Baryon electromagnetic form factors at BESIII

At BESIII, the electromagnetic form factors (EMFFs) and the pair production cross sections of various baryons have been studied. The proton EMFF ratio |GE/GM| is determined precisely and
line-shape of |GE| is obtained for the first time. The recent results of neutron EMFFs at BESIII show great improvement comparing with previous experiments.
Cross sections of various baryon pairs ($\Lambda, \Sigma, \Xi, \Lambda_c$) are studied from their thresholds. Anomalous enhancement behaviour on the Lambda and Lambdac pair are observed. The relative phase of EMFFs for $\Lambda$ and $\Sigma^+$ are measured for the first time. Besides, the production cross sections of spin 3/2 baryons are studied and the effective form factors are determined.

Speaker: Prof. Souvik Maity

14:40 Production of Hyperons, Charmed Baryons, and Hadronic Molecule Candidates in Neutrino–Proton Scattering

We investigate the production of hyperons, charmed baryons, and potential hadronic molecular states in neutrino–proton ($\bar{\nu}_\mu p$) scattering, a process characterized by a particularly clean final state. Employing effective Lagrangians, chiral perturbation theory, and a hadronic molecular model, we perform theoretical calculations for several relevant channels, including those leading to the formation of the hadronic molecular candidate $(\bar{D}N)$. Our results indicate that future neutrino facilities could serve as a complementary platform for exploring exotic baryonic states and provide valuable insights into the dynamics of strong interactions in the strange and charm sectors.

Speaker: Kai-Sa Qiao (Institute of Theoretical Physics, Chinese Academy of Sciences)

14:55 Measurement of Differential Cross-Section for the K^-p -> K^+Xi^- Reaction and Polarizations of Xi^- in (K^-, K^+) Reactions from Proton and Carbon at 1.8 GeV/c

The (K^-, K^+) reaction serves as a clean probe for investigating Lambda and Sigma resonances in the KN and KXi channels. In the absence of a double-strangeness meson, single-meson exchange in the t-channel is not permitted. However, a forward enhancement has been observed, indicating that interactions involving high-spin Lambda and Sigma resonances in the s- and u-channels play a vital role. Exploring this area provides valuable insights into the significance of strangeness in hadronic production channels.

We have measured the differential cross-section and the polarization of Xi in the forward region of 0.8 < cos θ*_{K^+} < 1.0 for the (K^-, K^+)Xi reaction at a beam momentum of 1.8 GeV/c using the J-PARC E42 detector on both proton and carbon targets. The sequential decays of Xi and Lambda were reconstructed using HypTPC.

In this presentation, we will share our preliminary results on the differential cross-section and polarization of Xi in the reactions p(K^-, K^+)Xi and 12C(K^-, K^+)Xi. For the proton target, we will also compare our findings with recent theoretical predictions.

Speaker: 병민 강 (Korea University)

15:10 Hyperon physics at BESIII

With the large datasets on 𝑒+𝑒−-annihilation at the 𝐽/𝜓 and 𝜓(3686) resonances collected at the BESIII experiment, multi-dimensional analyses making use of polarization and entanglement can shed new light on the production and decay properties hyperon-antihyperon pairs. In a series of recent studies performed at BESIII, significant transverse polarization of the (anti)hyperons has been observed in 𝐽/𝜓 or 𝜓(3686) $\to \Lambda \bar{\Sigma}$, $\Sigma \bar{\Sigma}$, $\Xi \bar{\Xi}$. The decay parameters for the most common hadronic weak decay modes were measured, and due to the non-zero polarization, the parameters of hyperon and antihyperon decays could be determined independently of each other for the first time. Comparing the hyperon and antihyperon decay parameters yields precise tests of direct, Δ𝑆 = 1 CP-violation that complement studies performed in the kaon sector.

Speaker: Yupeng Pei (University of Science and Technology of China (USTC))

15:25 Charmed baryon decays at Belle and Belle II

Singly charmed baryons, composite particles containing one charm quark and two lighter quarks, offer a unique system for studying dynamics of the strong and weak interaction and interplay between them. The Belle and Belle II experiments have conducted extensive studies on these particles, including branching fraction measurements, searches for rare and previously unobserved decay modes, and searches for CP violation. We present the first observations of several Cabibbo-favored and singly Cabibbo-suppressed $\Xi_c$ decays, along with precise branching fraction measurements of other $\Xi_c$ and $\Lambda_c$ decays. In addition, we report the first measurements of CP asymmetries in three-body singly Cabibbo-suppressed decays of charmed baryons.

Speaker: Jaeyoung Kim (BELLE (BELLE II Experiment) (Yonsei University))

14:00 → 15:40 Parallel Session C: Hadrons from heavy-ion collisions 1

14:00 Hadron Production in High-Energy Heavy-Ion Collisions

A variety of information can be extracted from hadrons observed in high-energy heavy-ion collisions. Thermodynamic properties such as the equation of state and viscosity of the quark matter produced have been discussed based on the collective flow of hadrons. Moreover, recent high-statistics and high-precision experimental results have even enabled discussions on hadronic interactions as well. What is crucial here is to describe the dynamics of high-energy heavy-ion collisions, for which relativistic hydrodynamic models are now widely employed. Within the framework of relativistic hydrodynamics, we focus particularly on hadronization and final state interactions, and discuss hadron production. Special attention here will be given to the production of resonances and exotic hadrons. Furthermore, we will also address the effects of magnetic fields on hadron production by employing relativistic magnetohydrodynamics that incorporates the electromagnetic fields generated immediately after the collision.

Speaker: Chiho Nonaka

14:20 Femtoscopic study using pA and AA collisions at J-PARC

The short-range component and density dependence of the ΛN interaction are crucial for understanding hyperons in neutron stars, yet remain poorly constrained experimentally. While the long-range part is limited by the ⁵ΛHe binding energy, short-range uncertainties persist. Large-source-size AA collisions, such as STAR-BESII, are mainly sensitive to the long-range region, whereas the small-source-size pA collisions in the J-PARC E88 experiment are highly sensitive to the short-range part, making them a powerful probe.

E88’s primary goal is to measure the in-medium modification of the φ meson via e⁺e⁻ and K⁺K⁻ pair measurements. Using the hadron detection system, we will also conduct α–Λ femtoscopy as a byproduct. The α particle’s spin and isospin of zero, along with its twice-normal nuclear density, allow direct constraints on the density dependence of the ΛN interaction. At √sNN ≈ 10 GeV, α yields in pA collisions are 100–1000 times higher than in high-energy collisions, enabling high-statistics measurements.

Future plans at J-PARC-HI include high-statistics α–hyperon femtoscopy and polarized-proton femtoscopy for partial-wave analysis. This presentation will outline the femtoscopy program at J-PARC, highlighting the complementary roles of E88 (short-range) and J-PARC-HI (long-range) measurements.

Speaker: Yudai Ichikawa

14:40 Overview of Hadronic Resonances in Ultrarelativistic collisions at the LHC

Results from RHIC and the LHC have revealed quark-gluon plasma (QGP)-like phenomena not only in heavy-ion (AA) collisions but also in high-multiplicity pp and p–Pb systems. These observations challenge traditional theoretical models and blur the line between small- and large-system dynamics.

Short-lived hadronic resonances offer sensitive probes of the medium created in such collisions. For example, while φ mesons are strangeness-neutral, their production mechanisms differ across models: QCD-inspired string models require associated strangeness production, whereas thermal QGP models allow for strangeness-neutral production. Thus, φ meson yields encode model-dependent strangeness behavior. Furthermore, comparing resonances with different lifetimes provides an excellent probe of the hadronic phase produced in QGP(-like) paradigms, and potential re-scattering effects.

This talk presents multi-differential resonance measurements across different systems and energies at the LHC, compared to Monte Carlo models spanning both QCD- and QGP-like scenarios, to explore where each paradigm dominates.

Speaker: Adrian Fereydon Nassirpour (Sejong University (KR), on behalf of the ALICE Collaboration)

14:55 Quantum correlation and entanglement in hyperon-antihyperon systems in electron-positron annihilation

Hyperon-antihyperon pairs produced in high energy electron-positron annihilation are promising systems for the study of quantum information properties. We make an analysis of some types of quantum correlations, Bell nonlocality, quantum steering and discord, in hyperon-antihyperon systems produced in electron-positron annihilation through J/\psi decay. The behaviors of these quantum correlations differ from those in elementary particle-antiparticle systems such as the top quark and tau lepton due to the polarization effect. The hierarchy of quantum correlations is examined and partially confirmed in hyperon-antihyperon systems: Bell Nonlocality \subset Steering \subset Entanglement. We also investigate the effect of the electromagnetic form factors of hyperons on four types of quantum correlations.

Speaker: Prof. Qun Wang (University of Science and Technology of China)

15:10 Measurement of Ξ(1530)0 production in pp collisions with ALICE

The measurement of resonances provides a tool to study the hadronic phase, the phase between chemical and kinematic freeze-out in the evolution of the quark-gluon plasma (QGP). Baryonic resonances, such as $\Xi(1530)^0$ with relatively long lifetime ($\sim$ 22 fm/c), serve as key probes to investigate the rescattering and regeneration effects inside the hadron resonance gas by comparing to the short-lived resonances and various models across collision systems. In particular, the study of $\Xi(1530)^0$ (S=-2) can provide insights into the evolution of strangeness. This presentation will discuss the results of $\Xi(1530)^0$ production in pp collisions at 13 and 13.6 TeV measured by ALICE at the LHC. These measurements will serve as a benchmark for future $\Xi(1530)^0$ measurements in larger collision systems.

Speaker: Minjae Kim (Pusan National University (KR))

15:25 $\phi$ and $\Omega$ production via recombination of parton showers in heavy ion collisions

We investigate the production of $\phi$(1020) mesons and $\Omega$ (1672) baryons in lead-lead(Pb-Pb) collisions at $\sqrt{s_{NN}}=5.02$ TeV. Thermal partons in the quark-gluon plasma (QGP) are generated based on the blast-wave model while parton showers are created from jet partons generated by HIJING by using a subroutine in PYTHIA. To describe the hadronization process, we employ a hybrid model that incorporates both recombination of parton showers and remnant string fragmentation. The analysis is carried out on an event-by-event basis, allowing for a detailed examination of hadron formation dynamics in the dense medium created by ultrarelativistic heavy-ion collisions. We also consider the production of the $\phi$ and $\Omega$ from strange quarks in the quark-gluon plasma by coalescence and discuss their yields and transverse momentum distributions.

Speaker: Kyong Chol Han (Prairie View A & M University)

14:00 → 15:40 Parallel Session D: Structure of hadrons 1

14:00 Precise determination of nucleon gravitational form factors using dispersion relations

Being closely connected to the origin of the nucleon mass, the gravitational form factors of the nucleon have attracted significant attention in recent years. We present the first model-independent determinations of the gravitational form factors of the pion and nucleon at the physical pion mass, using a data-driven dispersive approach. The socalled "last global unknown property" of the nucleon, the D-term, is determined to be $-3.38_{-0.35}^{+0.34}$. The root mean square radius of the scalar trace density inside the nucleon is determined to be $(0.97 \pm 0.03)$ fm. Notably, this value is larger than the proton charge radius, suggesting a modern structural view of the nucleon where gluons, responsible for most of the nucleon mass, are distributed over a larger spatial region than quarks, which dominate the charge distribution, indicating that the radius of the trace density may be regarded as a confinement radius. We also predict the nucleon angular momentum and mechanical radii, providing further insights into the intricate internal structure of the nucleon.

Based on the following two papers:
Nature Commun. 16 (2025) 6979; arXiv:2507.05375 [hep-ph].

Speaker: Prof. Feng-Kun Guo (Insitute of Theoretical Physics, Chinese Academy of Sciences)

14:20 Gravitational form factors of baryons in a spectator diquark model

Energy momentum tensor (EMT) expresses the interaction between the gravitation and the matter fields, in which the scattering off the graviton is a natural but infeasible probe. However, the EMT can be accessed indirectly through electromagnetic interactions in quantum chromodynamics. The matrix elements of the local EMT operator are parametrized by gravitational form factors, which are subsequently related to the generalized parton distributions. Within the diquark spectator model, we investigate the gravitational form factors of baryons. We consider all the feasible pairs of quark-diquark systems to understand the behavior of each constituent quark flavor of strange and non-strange baryons.

Speaker: Ms Navpreet Kaur (Dr. B.R. Ambedkar National Institute of Technology Jalandhar, India.)

14:35 Gravitational form factors of the nucleon via the Skyrme model based on scale-invariant chiral perturbation theory

Recently, the gravitational form factors (GFFs) of the nucleon have been extensively studied both theoretically and experimentally, with the aim of deepening our understanding of its internal structure. However, many details remain unclear, especially the connection between the GFFs and the non-perturbative aspects of QCD.

In our study, we focus on the role of the scale anomaly in nucleon GFFs. To investigate this, we analyze the nucleon using the Skyrme model based on scale-invariant chiral perturbation theory, in which the pion and a scalar meson are introduced to capture the effects of the current quark mass and gluonic quantum contributions to the scale anomaly, respectively. In this talk, we will discuss how the scale anomaly influences the GFFs—particularly the D(t) form factor—and explore its impact on the stress distribution and internal forces inside the nucleon.

Speaker: Mamiya Kawaguchi

14:50 Advances in Lattice Methodologies for Determining LCDAs: From Mesons to Baryons

The lattice QCD computation of parton distributions within the framework of large momentum effective theory (LaMET) constitutes a first-principles approach to studying hadron structures. Building upon preceding studies on meson systems, we have developed and partly implemented lattice methodologies for calculating the leading twist LCDAs of light baryons under the LaMET formalism over the past few years. In this talk, we will introduce our series of works on the ab initio determination of leading-twist LCDAs of light baryons and present preliminary numerical results. We will discuss the complexities involved in lattice calculations of baryonic systems compared to mesonic systems and report some techniques developed and employed recently to achieve physical results for the more intricate baryonic systems, including special operator selections, the hybrid renormalization scheme, and Fourier inversion strategies.

Speaker: Mr Haoyang Bai (IHEP, CAS)

15:05 x-dependent Light Baryon LCDAs from Lattice QCD

We present the results of lattice QCD calculation of all leading-twist x-dependent Light-cone Distribution Amplitudes (LCDAs) for baryons in light octet, within the framework of Large-momentum Effective Theory (LaMET). We implement a novel Hybrid renormalization scheme for baryon nonlocal operators, and perform simulations at 4 different lattice spacings a = {0.052, 0.068, 0.077, 0.105} fm, achieving reliable and precise results of x-dependent baryon LCDA. To access the large momentum regime and facilitate matching to light-cone, we simulate the quasi-Distribution Amplitudes (quasi-DAs) with hadron momenta Pz of about 1~3 GeV. The numerical calculations employ CLQCD ensembles with stout smeared clover fermions and a Symanzik gauge action, and several new techniques are also developed to improve the extrapolation and inversion in matching procedure. We present the resulting momentum-fraction distributions for the two light quarks in the light baryon.

Speaker: Mr Mu-Hua Zhang (Shanghai Jiao Tong University)

15:20 Multipole structure of Nucleon tensor form factors in the chiral quark-soliton model

The tensor form factors of the nucleon provide essential information
for understanding its internal spin structure. The monopole tensor
form factor at $Q^2=0$ is identified as the nucleon tensor charge,
which corresponds to the first moment of the leading-twist transverse
parton distribution function $h_1(x)$. While transversity has been
extensively studied both theoretically and experimentally, other
tensor form factors have received much less attention. In this talk,
we present recent results for the nucleon multipole tensor form
factors calculated within the framework of the chiral quark-soliton
model. The framework is based on the effective dynamics arising from
spontaneous chiral symmetry breaking and the mean-field description of
the nucleon at leading order in the large-$N_c$ limit. We find that
the tensor charge ($g_{T}^{u-d}=0.99$) and the tensor anomalous
magnetic moment ($\kappa_{T}^{u+d}=7.61$) are dominated by valence
quark contributions, whereas the tensor quadrupole moment
($Q_{T}^{u-d}=-7.02$) receives a significant contribution from the sea
quarks. We also explore the dependence of these moments on the soliton
size and the pion mass, and find the tensor nature of the nucleon are
fully relativistic. The results are in good agreement with available
lattice QCD data and provide predictions for unmeasured
quantities.

Speaker: 남용 김 (Inha University)

15:40 → 16:10 Coffee break

16:10 → 18:00 Parallel Session A: Spectroscopy of hadrons 1

16:10 J/Psi Photoproduction at the Threshold with GlueX

High-statistics total cross sections for the vector meson photoproduction at the threshold: gp-->\omega p (from A2 at MAMI and ELPH), gp--> \phi p (from CLAS6 at JLab and LEPS at SPring-8), and gp-->J/\psi p (from GlueX at JLab) allow one to extract the absolute value of vector meson nucleon scattering length using Vector Meson Dominance (VMD) model. The ``young’’ vector meson hypothesis may explain the fact that the obtained scattering length value for the nucleon.
\phi-meson compared to the typical hadron size of approximately ~1 fm indicates that the proton is more transparent for the \phi-meson compared to the \omega-meson and is much less transparent than the J/\psi-meson. The new CLAS12 \phi-meson electroproduction data allows one to extend our recent study to a high Q2 range. The extended analysis of \Upsilon-meson photoproduction using quasi-data from the QCD approach is in perfect agreement with the light-meson findings using experimental data.
Recent high-statistical J/\psi photoproduction cross sections measured by the GlueX Collaboration allow one to search for the exotic Pc(4312) state observed by the LHCb Collaboration. The fits show that destructive interference involving a S-wave resonance and associated non-resonance background produces a sharp dip structure approximately 77 MeV below the LHCb mass, in the same location as a similar structure is seen in the data. The interference between open charm and gluon exchange may (by some accident) produce a dip, but there is room for resonance.
Future high-quality experiments by EIC and EicC will have the opportunity to evaluate cases for J/\psi- and \Upsilon-mesons. It allows one to understand the dynamics of c-bar-c and b-bar-b production at the threshold and to look for the effect of LHCb heavy quark exotic states. The ability of J-PARC to measure pi- p-->\phi n and pi-p-->J/\psi n, which are free from the VMD model, is evaluated.

Speaker: Igor Strakovsky (The George Washington University)

16:30 J/ψ Production in π−p Reaction near Threshold

This presentation will introduce a new proposal (J-PARC P111) focused on studying the production of $J/\psi$ in $\pi^-p$ reactions from the threshold up to W=4.64 GeV. Investigating $J/\psi$ production will offer valuable insights into the mechanisms of $c\overline{c}$ pair creation in pion-induced processes, particularly in relation to hidden-charm pentaquark states.

We plan to measure the total cross sections for the exclusive reaction $\pi^-p \to J/\psi n$ using the E50 spectrometer, which will be enhanced with new electron and muon detectors. This measurement aims to provide the first experimental data on $\pi^-$-induced $J/\psi$ production near the threshold. Additionally, the P111 experiment will measure total cross sections for open-charm production channels in $\pi^-p$ reactions, complementing the $J/\psi p$ channel.

This presentation will outline the proposal P111, with a special emphasis on its significance for the search for hidden-charm pentaquarks.

Speaker: Sun-Young Ryu

16:45 Exploring Multiple Interpretations of $T_{cc}(3875)^+$ from the Experimental Distributions

In 2022, the LHCb collaboration reported an exotic hadron, $T_{cc}(3875)^+$, based on a peak structure observed in the $D^0D^0\pi^+$ invariant-mass line shape. Because this peak lies just below the $D^{*+}D^0$ threshold, $T_{cc}(3875)^+$ is often analyzed as a weakly bound hadronic molecule of $D$ and $D^*$ mesons; nonetheless, the possibility that it exists as a compact $cc\bar u\bar d$ tetraquark cannot be excluded.

In this work, we construct a coupled-channel model for $D^{*+}D^0–D^{*0}D^+$ scattering that explicitly includes a bare $T_{cc}$ field, thereby allowing for mixing between molecular and compact components rather than assuming a purely molecular state. Our model successfully reproduces the LHCb $D^0D^0\pi^+$ line shape and shows that three distinct scenarios—each corresponding to a different internal structure—can describe the experimental data with comparable accuracy. We then test the consistency of these scenarios against the $D^0D^0$ and $D^0D^+$ channel distributions reported by LHCb and discuss the validity of each. Given the current experimental resolution and statistical uncertainties, it remains impossible to determine definitively whether $T_{cc}(3875)^+$ is predominantly a compact tetraquark or a hadronic molecule; our study demonstrates that multiple interpretations remain viable.

Speaker: Shota Ampuku (Nagoya university)

17:00 P-wave $c\bar{c}$ meson contributions in exotic hadrons

Since $X(3872)$ was reported by the Belle collaboration in 2003, exotic hadrons containing charm quarks have been reported almost every year. Many of these are hidden charm exotic hadrons. In this study, we analyze the exotic hadrons $X(3860)$, $X(3872)$, and $Z(3930)$ with the same quantum number as the P-wave $c\bar{c}$ meson $\chi_{cJ}(2P)$ as superposition states of hadronic molecular states and bare $c\bar{c}$ states.

Speaker: Kotaro Miyake (Nagoya University)

17:15 Charmed baryon decays at BESIII

BESIII has accumulated 4.5 $fb^-1$ of e+e- collision data in the 4.6 to 4.7 GeV energy range, which provides the largest dataset of $\Lambda_c - \bar{\Lambda_c}$ pairs in the world. Our presentation will include the observation of a rare beta decay $\Lambda_c^+ \to n e^+ \nu$ with a Graph Neural Network and the first measurement of the decay asymmetry in the pure W-boson-exchange decay $\Lambda_c^+ \to \Xi^0 K^+$, as well as the branching fraction measurements of the
inclusive decays $\Lambda_c^+ \to X e^+ \nu$ and $\bar{\Lambda_c} \to \bar{n} X$. Furthermore, we will present results of the partial wave analysis of $\Lambda_c^+ \to \Lambda \pi^+ \pi^0$, and $\Lambda_c^+ \to \Lambda \pi^+ \eta$. Our presentation will also include branching fraction measurements of Cabibbo-suppressed decays, including $\Lambda_c^+ \to p \pi^0$, and the measurements of $K_S-K_L$ asymmetries in the $\Lambda_c^+$ decays.

Speaker: Mr Xudong Yu (Peking University)

17:30 Spectroscopic study of baryons using high-momentum hadron beams at J-PARC.

Hadrons are composite particles of quarks and gluons interacting with each other. Quantum chromodynamics (QCD) plays an essential role in describing the interactions between quarks and gluons. However, low-energy QCD dynamics such as formation of hadrons are not clearly explained yet. Understanding the formation of hadrons is one of the fundamental goals of hadron physics. Recent experimental results reveal the rich properties of excited states of hadrons [1]. In order to understand the nature of excited states, it is necessary to investigate the effective degrees of freedom of hadrons and their interaction. Diquark correlation can be essential effective degrees of freedom for describing the hadron structure. Spectroscopy of charmed and strange baryons such as $\Lambda_c$, $\Xi$ and $\Omega$ can provide information of the diquark correlation. Comprehensive systematic studies of those baryons are expected to reveal and clarify the effective degrees of freedom and spin-dependent forces to describe the hadron structure. The high-intensity and high-momentum beams available at J-PARC give us many opportunities to investigate the structure of hadrons in which charm and strange quarks play an important role. At the current J-PARC hadron facility, the high-momentum beam line for providing high-intensity secondary beams, called $\pi$20 beam line, are being constructed for the spectroscopic experiment of charmed baryons [2]. In the extension of the hadron facility [3], we plan to construct the high-momentum beam line which is dedicated for providing separated $K^-$ up to 10 GeV/$c$, called K10 beam line. We will conduct spectroscopic experiments of $\Xi$ and $\Omega$ baryons [4] at K10. High-intensity hadron beams with high momentum which are provided by J-PARC are essential to explore nature of hadrons for understanding the low energy QCD dynamics.
[1] S. K. Choi et al., Phys. Rev. Lett. 91, 262001 (2003)., R. Aaij et al., Phys. Rev. Lett. 121, 162002 (2018).
[2] H. Noumi et al., J-PARC Proposal E50 (2012).
[3] “Extension of the J-PARC Hadron Experimental Facility: Third White Paper”, arXiv:2110.04462 [nucl-ex]
[4] M. Naruki and K. Shirotori et al., J-PARC Proposal E97 (2014). K. Shirotori et al., J-PARC Proposal P85 (2021).

Speaker: Kotaro Shirotori (Research Center for Nuclear Physics (RCNP) Osaka University)

16:10 → 18:00 Parallel Session B: Hadrons at finite density & temperature 1

16:10 What neutron stars say about the properties of strong interaction

The existence of neutron stars provide us with a challenge and a
possibility to study strong interaction, too. At the center of
neutron stars the densities can reach 6-8 times the normal nuclear densities,
and these densities cannot be studied in terrestrial experiments.
Therefore, it provides us with constraints for the properties of the cold,
dense strongly interacting matter.
The existence of quark matter inside the heaviest neutron stars has
been the topic of numerous recent studies, many of them suggesting
that a phase transition to strongly interacting conformal matter
inside neutron stars is feasible. Here we examine this hybrid star
scenario using a soft and a stiff hadronic model, a constituent
quark model with three quark flavours, and applying a smooth
crossover transition between the two. Within a Bayesian framework,
we study the effect of up-to-date constraints from neutron star
observations on the equation-of-state parameters and various
neutron star observables. We find, consistently with other studies, that a
peak in the speed of sound, exceeding 1/3, is highly favoured
by astrophysical measurements.

Speaker: György Wolf

16:30 A study of neutron star property based on the Parity-Doublet-Models

I will summarize our recent works in which we studied neutron star property based on Parity Doublet Models. In the low-density region, we construct the EoS using hadronic models based on the parity doublet structure with the chiral invariant mass of nucleons. In the high density region, the EoS is obtained in an NJL-type quark model. By connecting two EoSs with assuming the quark-hadron crossover or first order phase transition, we construct unified EoSs for dense matter. We then derive the M-R relation of neutron stars from the unified EoSs and compare the result with the observational constraints to obtain an allowed range for the chiral invariant mass.

Speaker: Masayasu Harada (Nagoya University)

16:50 A dual description of quarks and baryons: Quarkyonic matter within a relativistic quark model

We investigate a dual description of quarks and baryons in dense QCD matter, focusing on the quarkyonic regime. Based on the momentum–shell picture [Phys. Rev. D 104 (2021) 074005; Phys. Rev. Lett. 132 (2024) 112701], we adopt a relativistic confinement potential of the scalar-vector harmonic oscillator type to describe confined quarks and explore quark–hadron continuity at high densities. We highlight the role of quark saturation in baryonic matter and calculate the nucleon chemical potential and the speed of sound. Furthermore, by incorporating realistic nucleon-nucleon interactions using the quark-meson coupling model [Phys. Rev. D 110 (2024) 113001], we demonstrate that the dual description can be consistently connected to nuclear matter phenomenology. This study provides a new theoretical perspective on the possible realization of quarkyonic matter and quark–hadron continuity in strongly interacting matter.

Speaker: Tsuyoshi Miyatsu

17:05 Density-induced Chiral Mixing and Mass Degeneracy of Parity Doublets in Di-lepton Spectra

The spectral functions of chiral partners should become degenerate when the QCD chiral symmetry is restored. The axial-vector spectra are experimentally more challenging to construct than those of vector mesons that directly couple to virtual photons and then to dileptons. Chiral mixing of the vector with axial-vector mesons is thus a key phenomenon to probe in-medium modifications of vector spectrum due to the onset of chiral symmetry restoration carried by the axial-vector counterpart. The mixing effect is expected to be stronger at higher density due to a mechanism driven by chiral anomalies [1], in striking contrast to the vanishing mixing at chiral crossover driven by thermal pions [2]. This feature encourages us to perform the experimental search in the high-density regime, where the recent experimental trend has begun to shift toward.
We propose that experiments at medium energies with paying attention to the new mixing mecha- nism, may provide a direct evidence of the chiral symmetry restoration. In this presentation, we focus on the density-induced mixing and the spectral functions of φ and its chiral partner f1(1420). We present the invariant mass distribution of dileptons using a transport approach developed in [3, 4] under the conditions of the J-PARC E16 experiment as a prime example.
We find that the f1(1420) meson is visible with 2 to 3 σ credibility in dilepton production in a range of mixing strength in our study when the expected statistics at E16 Run-2 are utilized [5]. We advocate that the E16 experiment at J-PARC has discovery potential for the mass degeneracy of chiral partners at finite density as a signature of chiral symmetry restoration.

Reference
[1] C. Sasaki, Signatures of chiral symmetry restoration in dilepton production, Phys. Let. B 801, 135172 (2020); C. Sasaki, Anomaly-induced chiral mixing in cold and dense matter, Phys. Rev. D 106, 054034 (2022).
[2] A. Sakai, M. Harada, C. Nonaka, C. Sasaki, K. Shigaki, and S. Yano, Probing the QCD phase transition with chiral mixing in dilepton production, 2308.03305, arXiv, nucl-th(2023).
[3] W. Cassing, and E. L. Bratkovskaya, Parton transport and hadronization from the dynamical quasi- particle point of view, Phys. Rev. C 78, 034919 (2008).
[4] P. Gubler, E. L. Bratkovskaya, and T. Song, φ meson properties in nuclear matter from dilepton spectra in a transport approach, EPJ Web Conf. 274, 07015 (2022).
[5] R. Ejima, P. Gubler, C. Sasaki, and K. Shigaki, Toward a direct measurement of partial restoration of chiral symmetry at J-PARC E16 via density-induced chiral mixing, Phys. Rev. C 111, 055201 (2025).

Speaker: Mr Ren Ejima (Hiroshima University (JP))

17:20 Octet baryon electroweak form factors in dense nuclear matter

Although the experimental information about the electroweak structure of the baryons and mesons in nuclear medium is limited, it is generally accepted that their structure is modified in a nuclear medium due to the change of the properties of quarks and gluons. Theoretical models are then fundamental for the understanding of environments with dense nuclear matter, from high energy nucleus-nucleus collisions to the cores of compact stars. We discuss here a framework that has been used to calculate electromagnetic and axial form factors of baryons in terms of the square transfer momentum $q^2= -Q^2$ and the density of the nuclear medium $\rho$. The electromagnetic and axial form factors of the octet baryons are determined by combining a covariant quark model that takes into account the meson cloud dressing of the baryon cores, developed for free space, with the quark-meson coupling model in the extension to the nuclear medium. The medium modifications of the octet baryon electromagnetic and axial form factors are calculated and discussed for the range of densities from $\rho=0$ up to $\rho=3 \rho_0$, where $\rho_0= 0.15$
fm$^{-3}$ is the normal nuclear matter density. We conclude that the nuclear medium modifies the baryon properties differently (quenched or enhanced), according to the mass and flavor content of the baryons. The numerical values for the electroweak form factors are used to calculate neutrino-baryon and antineutrino-baryon cross sections for baryons bound to nuclei and for dense nuclear matter. We conclude that, in general, the in-medium cross sections are reduced when compared with the cross sections in free space. The formalism can in the future be extended to the study of several baryon systems and applied to problems with astrophysical applications.

[1] G.~Ramalho, K.~Tsushima and M.~K.~Cheoun,
"Electroweak Form Factors of Baryons in Dense Nuclear Matter,"
Symmetry \textbf{17}, 681 (2025) [arXiv:2504.15660 [nucl-th]].

[2] G.~Ramalho, K.~Tsushima and M.~K.~Cheoun,
"Weak interaction axial form factors of the octet baryons in nuclear medium}," Phys. Rev. D \textbf{111}, 013002 (2025) [arXiv:2406.07958 [hep-ph]].

Speaker: Gilberto Ramalho (Soongsil University and OMEG Institute)

17:35 Pion properties in isospin-asymmetric nuclear matter using in-medium chiral perturbation theory

We compute the density dependence of in-medium pion properties, such as mass, wave function renormalization, and decay constant in the correlation function approach, and how they change under the influence of isospin-asymmetric nuclear matter. To this end, we use in-medium chiral perturbation theory to compute the relevant Feynman diagrams up to two-loop diagrams. Our results show that the isospin asymmetry of the nuclear matter splits these quantities into three separate values, corresponding to the three pions. Consequently, the tendency of each in-medium pion mass, wave function renormalization, and decay constant is dependent on the density and the neutron-to-proton ratio $\rho_n$/$\rho_p$ of nuclear matter. We also derive an in-medium Gell-Mann–Oakes–Renner relation which is valid for isospin-asymmetric nuclear matter and investigate to what extent it holds within our calculations.

Speaker: Kihong Kwon (Institute of Science Tokyo)

16:10 → 18:00 Parallel Session C: Recent developments in QCD 1

16:10 Universality and emergent effective fluid from jets and string breaking in the massive Schwinger model using tensor networks

We analyze the correlation between the energy, momentum and spatial entanglement produced by two luminal jets in the massive Schwinger model. Using tensor network methods, we show that for m/g > 1/π, in the vicinity of the strong to weak coupling transition, a nearly perfect and chargeless effective fluid behavior appears around the mid-rapidity region with a universal energy-pressure relationship. The evolution of energy and pressure is strongly correlated with the rise of the spatial entanglement entropy, indicating a key role of quantum dynamics. Some of these observations may be used to analyze high multiplicity jet fragmentation events, energy-energy and energy-charge correlators at current collider energies.Presentation is based recent work done in collaboration with Romuald A. Janik, Marek Rams and Ismail Zahed (https://arxiv.org/pdf/2502.12901)

Speaker: Prof. Maciej Nowak (Jagiellonian University)

16:30 Nonlocal Effective Theory for Heavy Mesons from the QCD Instanton Vacuum

We present an instanton-vacuum approach to heavy–light mesons that retains the nonlocal heavy-quark kernel beyond the static limit. Bosonization yields an effective heavy-meson field with momentum-dependent vertices, and the bound state follows from a three-dimensional Bethe–Salpeter equation with controlled $1/N_c$ and $1/m_Q$ systematics. We compute decay constants, masses, and radiative form factors from the modified Feynman vertex.

Speaker: KIHOON HONG (Inha University)

16:45 Effective gluon operators for heavy-light systems in the instanton vacuum

We develop a framework for evaluating matrix elements of gluon operators between physical states of heavy–light systems within the instanton vacuum. Starting from the low-energy QCD partition function describing heavy and light quarks in the background of an $N_\pm$ instanton–anti-instanton ensemble, we derive an effective fermionic action that includes the interaction of a heavy and $N_f$ light quark flavors. This framework enables the computation of heavy–light meson and baryon matrix elements of quark operators in the $1/N_c$ expansion. In this approach, gluon operators are systematically represented in terms of effective fermionic operators within the single-instanton approximation.

Speaker: Nurmukhammad Rakhimov

17:00 Lattice studies of chimera baryons in Sp(4) gauge theory

We present lattice results on the masses and matrix elements of chimera baryons, the fermionic bound states composed of hyperquarks transforming in the fundamental and antisymmetric representations of the gauge group in Sp(4) gauge theory. In the context of the composite Higgs model, an extension of the standard model of particle physics, some of these chimera baryons serve as top partners responsible for generating the large top-quark mass through partial compositeness. We measure the mass spectrum of the low-lying chimera baryons in the quenched approximation, and carry out the continuum and massless extrapolations borrowing the idea of QCD heavy baryon chiral perturbation theory. We also consider fully dynamical calculations for several choices of lattice bare parameters, and extract the masses and matrix elements by employing a newly developed spectral density analysis method.

Speaker: Dr Jong-Wan Lee (Institute for Basic Science (IBS))

17:15 Implications of the gluon mass gap in QCD observables

It is now firmly established that the gluon propagator in Landau gauge exhibits a mass gap, $m_\textrm{gap}$, originating in the action of the Schwinger mechanism in the gauge sector of QCD. In this work, we show that this mass gap leads to a screening of the gluon in the deep infrared: observables are insensitive to the details of the gluon propagator at momenta below $m_\textrm{gap}$. This is shown explicitly for two observables that are characteristic of QCD: the confinement-deconfinement transition temperature, $T_c$, and the pion decay constant, $f_\pi$. The value of the physical mass gap is determined as the real part of the first non-trivial singularity of the gluon propagator in the complex plane. This value can be estimated through a minimal fit of the propagator, which preserves its perturbative and infrared behaviors, and whose parameters have a clear physical interpretation. The result obtained in this way agrees with the scale below which variations of the gluon propagator do not affect $T_c$ and $f_\pi$.

Speaker: Mauricio Narciso Ferreira (Institute for nonperturbative physics and School of Physics, Nanjing University)

17:30 Quantum simulation of baryon scattering in SU2 lattice gauge theory

One of the central goals of high-energy physics is to understand scattering processes and what they reveal about the underlying theory. This is traditionally framed within the $S$-matrix picture, which cannot, in general, be accessed through Euclidean lattice methods. However, with recent advances in quantum technologies and computational methods, the prospect of studying real-time processes in gauge theories is becoming increasingly realistic. At present, simulations of scattering events remain limited to lower-dimensional theories and modest energy ranges. In this talk, we present the first real-time simulations of hadronic scattering in (1+1)D SU(2) gauge theory with matter, performed using tensor network techniques. We investigate processes in sectors with conserved global baryon number $B = 0, 1, 2$. While the $B = 0$ sector exhibits dynamics closely resembling those of a U(1) theory, the higher-$B$ sectors display qualitatively new behaviour. In particular, we find that local baryon number spreads during scattering in a manner analogous to entanglement entropy growth. We conclude by discussing how these results contribute to a fully non-perturbative picture of particle production.

Speakers: Joao Lourenco Henriques Barata, Juan Hormaza (Universidad Nacional de colombia, Manizales, Colombia), Wenyang Qian (University of Santiago de Compostela)

16:10 → 18:00 Parallel Session D: New facilities & instrumentation 1

16:10 Advanced Instrumentation for Rare Isotope Beam Experiments at CENS

The Center for Exotic Nuclear Studies (CENS) has developed a diverse set of experimental instruments to enable precision measurements with rare isotope beams. These systems address key challenges in nuclear astrophysics and structure studies, including low-intensity beam conditions, inverse kinematics, and complex reaction channels. Recent developments include beam purification systems, cryogenic and active targets, gas jet targets, segmented detectors, fast-timing detectors and integrated setups for particle-γ coincidence measurements. Together, these devices are designed as a modular platform adaptable to a wide range of experimental requirements, enabling direct reaction measurements and spectroscopic studies with improved resolution and detection efficiency. Commissioned at RAON and compatible with international radioactive isotope facilities, the CENS instruments significantly expands the experimental reach for rare isotope science.

Speaker: Sunghoon(Tony) Ahn

16:30 Status report of the RENE experiment

The Reactor Experiment for Neutrinos and Exotics (RENE) is designed to investigate sterile neutrinos in the region of Δm² ~ 2 eV².
The prototype detector consists of a cylindrical target filled with 0.5 tons of gadolinium-loaded liquid scintillator (Gd-LS), surrounded by a box-shaped gamma catcher containing 1.5 tons of liquid scintillator (LS), and equipped with two 20-inch PMTs.
The baseline distance from the reactor core is approximately 24 meters.
The experiment is currently in the commissioning phase, with the prototype detector installed on the ground level to prepare for the first data-taking run at the tendon gallery of the Hanbit Nuclear Power Plant.
This presentation will report on the current status of preparations for the RENE experiment.

Speaker: Dong Ho Moon (Chonnam National University (KR))

16:50 Detector performance of the RENE experiment

The RENE (Reactor Experiment for Neutrinos and Exotics) experiment aims to search for sterile neutrinos in theΔm² ≈ 2 eV² region at a baseline of about 23 m from the reactor core. The prototype detector consists of a 0.5-ton cylindrical target filled with 0.5% gadolinium-loaded liquid scintillator (GdLS), surrounded by a 1.5-ton box-shaped gamma catcher with liquid scintillator (LS). The active volume is instrumented with two 20-inch photomultiplier tubes (PMTs). The detector is currently in the assembly and commissioning stage at a ground-level laboratory, where we are testing system stability and verifying operational readiness. As part of this commissioning process, performance studies have been carried out using calibration data and radioactive sources, providing insight into the detector’s energy response, calibration procedures, and background characterization. In this study, we performed a three-dimensional calibration using radioactive sources to evaluate the overall performance of a liquid scintillator based neutrino detector. Data collected at various positions inside the detector were used to examine the energy response and its position dependence, which were subsequently corrected to ensure a uniform response throughout the full detector volume. In this presentation, we will describe the calibration procedure, the obtained results, and how these have been applied to evaluate and improve the detector performance.

Speaker: Daeun Jung

17:05 Hyperon-Nucleon interactions at BESIII

With the existing 10 billion J/ψ events accumulated at BESIII, the high production of long-lived baryons in J/ψ decays serves as a novel source of hyperon beams, which open a unique opportunity for exploring the hyperon-nucleon interactions. By studying the interactions of these hyperons with the beam pipe and the inner tube of the MDC detector, the recent results achieved at BESIII, including interactions of $\Lambda p$, $\Sigma p$, and $\Xi n$, will be presented. Also, the perspectives at a future tau-charm factory will be discussed.

Speaker: Tao Luo

17:20 Search for Axion-Like-Particles in η meson decays with the HADES Detector

The High-Acceptance Di-Electron Spectrometer (HADES) operates at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, using pion, proton, and heavy-ion beams provided by the SIS-18 synchrotron [1]. In February 2022, the HADES Collaboration measured proton-proton collisions at 4.5 GeV kinetic energy using the upgraded setup as part of the FAIR-Phase0 program [2]. One of the key objectives of the HADES physics program is to test the predictions of the Standard Model and search for potential hints of new phenomena beyond current theoretical frameworks (BSM –Beyond Standard Model Physics). It can be experimentally accessible via particles in the MeV–GeV mass range, which are coupled to the Standard Model.

Recently, a new set of calculations were done which predicts a possible existence of Axion-Like-Particles with a mass $m_a$ = $O(1−100)$ MeV and $f_a$ = $O(1−10)$ GeV [3] with additional PQ-breaking contribution to their masses. In particular, by studying η meson decays into dilepton ($e^{+}e^{−}$) channels, we investigate the possible existence of an Axion-Like Particle (ALP) [4-5]. In this scenario, an intermediate state of the $\eta$ meson decay could involve the creation of a new particle through the sequence $\eta \to \pi^{+}\pi^{-} a (e^{+}e^{−})$. The particle is hypothesized to be an iso-scalar or axial-vector gauge boson, which may mediate a fifth force with couplings to Standard Model particles [6]. These studies are further motivated by observed anomalies in the invariant mass distribution of $e^{+}e^{−}$ pairs in nuclear transitions of $^8Be$ and $^4He$ nuclei [7-8]. These anomalies have been interpreted as evidence for the creation and decay of an intermediate particle with a mass of approximately 17 MeV/c${^2}$, and suppressed mixing with the neutral pion.

In this talk, we will discuss the general motivations for ALP studies, present our analysis methodology, and share preliminary results from data collected using the high-resolution HADES spectrometer.

Bibliography:
[1] G. Agakichiev et al. (HADES Coll.), Eur. Phys. J. A 41, 243 (2009).
[2] J. Adamczewski-Musch et al. (HADES Coll.) Eur. Phys. J. A 57, 138, 4 (2021).
[3] D. S. M. Alves and N. Weiner, JHEP 07, 092 (2018).
[4] D. S. M. Alves, Phys. Rev. D 103, 055018 (2021)
[5] D. S. M. Alves and S. Gonzalez-Solis, JHEP 07, 264 (2024).
[6] J. L. Feng et al., Phys. Rev. Lett. 117, 071803 (2016).
[7] A. J. Krasznahorkay et al., Phys. Rev. Lett. 116, 042501 (2016).
[8] A. J. Krasznahorkay et al., Phys. Rev. C 104, 044003 (2021).

Speaker: Dr Marcin Zielinski (Jagiellonian University (PL))

18:00 → 19:30 Poster

18:00 sPHENIX measurement of Open-Charm Baryon-to-Meson Ratios in p+p collisions at RHIC

sPHENIX is a state-of-the-art experiment at the Relativistic Heavy Ion Collider (RHIC),
dedicated on the study of heavy-flavor and jet physics. Its novel streaming-readout-capable,
precision tracking system allows for heavy-flavor measurements through high-statistics,
unbiased data samples with exceptional precisions. During the 2024 run, sPHENIX was fully
commissioned, collecting a sample of 100 billion unbiased p+p collisions and a further
sample of minimum-bias Au+Au collisions. The ongoing 2025 run is further enhancing the
dataset with high-statistics Au+Au collisions. This extensive p+p collision sample enables
heavy-flavor physics measurements in p+p collisions with orders of magnitude more statistics
than that previously available at RHIC. Notably, there has been no prior measurement of the
Lambda_c / D0 baseline in p+p collisions at RHIC energies. The large sPHENIX dataset now
enables the first exploration of key open questions, such as the hadronization mechanism of
baryons and the strange-to-light flavor meson ratio. We will present the status of the first
measurements of the Lambda_c / D0 ratio and the similarly unexplored D_s+ / D+ ratio in
p+p collisions.

Speaker: Mr Xudong Yu (Peking University)

18:02 Prospects for the Isolated Photon Transverse Single Spin Asymmetry with sPHENIX

Direct photon single spin asymmetries, 𝐴𝑁, have the advantage that they are not sensitive to final state effects and that the hard scattering process is predominantly quark-gluon scattering at RHIC energies.
Therefore, direct photons provide a clean probe to study the quark-gluon and tri-gluon correlations in single spin asymmetries, with the latter particularly hardly constrained at present.
The larger and more hermetic acceptance of sPHENIX compared to PHENIX is expected to improve the statistics of the previous direct photon AN measurements using the 2024 polarized proton-proton collisions that were recorded in sPHENIX.

Speaker: Jaein Hwang (Korea University)

18:04 Calibration of the HADES Electromagnetic Calorimeter with Leptons from Au+Au Collisions

The Electromagnetic Calorimeter (ECAL) is a key subdetector of the HADES (High Acceptance Di-Electron Spectrometer) experiment at SIS18, GSI Darmstadt. Its main purpose is the measurement of photons and electrons, enabling studies of neutral meson production, dielectron sources, and improved electron–hadron separation. A dedicated calibration campaign was performed using leptons from Au+Au collisions at 800, 400, and 200 AMeV, where precise momentum determination from the tracking detectors (MDC) and particle identification with the RICH, TOF, and RPC subsystems provided a clean reference for the ECAL response. The correlation between reconstructed electron momentum and calorimeter amplitude enabled the extraction of energy calibration functions for individual modules and the determination of the detector’s resolution across the full acceptance. Looking ahead, the calibrated ECAL will play a central role in the upcoming HADES pion-induced reactions on CH₂ and C targets, where it will be essential for reconstructing third-baryon and hyperon resonance decay channels in an energy scan from √s = 1.67 to 1.79 GeV.

Speaker: Antonín Opíchal (Nuclear Physics Institute of the CAS (CzAS))

18:06 Deblurring on triple-differential yield from 132,108Sn+124,112Sn @ 270 AMeV collision from SPiRIT

The triple-differential yield as functions of the transverse momentum, the rapidity and the azimuthal angle relative to the estimated reaction plane is a critical observable for the collective-flow analysis in heavy-ion collisions. However, the triple-differential yield can be degraded by not only methodology to estimate reaction plane direction but also imperfect detector performance such as the detection inefficiency and detector acceptance. Richardson-Lucy deblurring algorithm describes a method to restore the degraded intensity distributions and is widely used in various fields such as optics and astronomy. Inspired by this algorithm, the dedicated deblurring algorithm has been developed and applied to the analysis for $^{132,108} \rm Sn + ^{124,112}Sn$ at 270 AMeV by the SpiRIT Collaboration. In this presentation, we introduce the deblurring process using the Richardson-Lucy algorithm to restore the triple-differential yield and compare the results before and after deblurring process including flow parameter as an example of triple-differential yield.

Speaker: Jeonghyeok Park (Korea University)

18:08 Study on the phi-meson production via pi- p to phi n

In this study, we investigate the properties of the $\phi N$ interaction and aim to determine its scattering length. Although the $\phi NN$ coupling is expected to be OZI-suppressed, coupled-channel analyses and the ALICE experiment indicate that it can be sizable. We explore possible $N^{*}$ resonances that can be produced in this reaction. We employ an effective Lagrangian approach and consider various $N^*$ states in the s- and u-channels. However, the calculated total and differential cross sections do not reproduce the data near 2.15 GeV. To reproduce this feature, we introduce a new nucleon resonance and perform a fit, consistent with similar structures reported in photoproduction. In future work, we plan to compute the scattering length of this interaction and the SDMEs.

Speaker: Dayoung Lee

18:10 Neutron Irradiation Effects and Annealing Studies of SiPMs

Silicon Photomultipliers (SiPMs), composed of arrays of avalanche photodiodes operating in Geiger mode, are widely used in particle and nuclear physics experiments due to their compact size, magnetic-field insensitivity, and low operating voltage compared to conventional photomultiplier tubes. However, their performance can degrade under neutron irradiation, potentially affecting experimental accuracy. In this study, two SiPM types (Hamamatsu S13360 and S14160) were irradiated to investigate radiation-induced changes. During irradiation, LED-triggered signals were continuously recorded with a 500-MHz flash ADC to monitor variations in gain, baseline shift, and dark current rate. I–V characteristics were also measured before and after irradiation to evaluate leakage current and breakdown voltage shifts. Ongoing studies focus on annealing effects, which are expected to partially recover SiPM performance after irradiation. These results provide insights into the relative radiation tolerance, degradation mechanisms, and potential recovery behavior of SiPMs in high-radiation environments.

Speaker: JunHyung Park (Department of Physics, Kyungpook National University)

18:12 Development of a SiPM–Light Guide Readout System for the Barrel Imaging Calorimeter in the Electron–Ion Collider

The Barrel Imaging Calorimeter (BIC) of the ePIC detector at the upcoming Electron–Ion Collider (EIC) consists of silicon pixel layers for precise shower profile measurements and a high-granularity sampling calorimeter of lead absorbers interleaved with scintillating fibers for energy measurement. This work focuses on the readout development for the sampling calorimeter section, where a compact system coupling a light guide to a silicon photomultiplier (SiPM) has been designed to operate in a strong magnetic field with limited space. We report a comparative study of multiple readout configurations, focusing on photon collection efficiency, spatial uniformity, and linearity over a broad energy range. Beam tests with electron beams at KEK PF-AR and CERN PS T10 were performed, and the results are compared with Geant4 optical simulations incorporating measured material properties. In this talk, we present the comparison of beam test and simulation results to evaluate the performance of the SiPM–light guide readout and discuss its implications for integration into the BIC at the EIC.

Speaker: Bo Gyeong Seo (Kyungpook National University (KR))

18:14 Exploring Beauty Bound States: Mass Spectra and Decay Dynamics of B Mesons and $Bq\bar{q}\bar{q}$ Tetraquarks

The observation of exotic bottomonium-like states at Belle, BaBar, and LHCb motivates a detailed study of beauty-quark bound systems. We present a spectroscopy analysis of $B$ mesons and tetraquarks with quark content $b q \bar{q} \bar{q}$ in the diquark–antidiquark framework. Mass spectra are computed using a Cornell-type potential with color antitriplet–triplet configurations. Decay modes are examined via the factorization approach for $B$ mesons and Fierz rearrangements for tetraquarks. The results are compared with reported resonances, offering insights into the structure and dynamics of exotic hadrons in the beauty sector.

Speaker: Chetan Lodha

18:16 Production of the X(3872) in a $D\bar{D}*$ Molecular Scenario Dominated by an Color Octet-Octet Component

We investigate the production of the exotic hadron X(3872) within the coalescence model, assuming it is a $D\bar{D}^*$ molecular state. A basis transformation of the $D\bar{D}^*$ configuration shows that it is dominated $(\sim 90\%)$ by the $(q\bar{q})^{C=8} \otimes (c\bar{c})^{C=8}$ component, with a smaller color singlet-singlet component. Using this dominant color octet-octet configuration, we calculate the transverse momentum distribution of the X(3872). We also evaluate the yield ratio X(3872)$/\psi(2S)$ by combining our calculated $p_T$ spectrum of the X(3872) with the measured $\psi(2S)$ spectrum, enabling a direct comparison between two states of similar mass but different internal structures. Our results provide theoretical predictions that can be tested in future high-precision measurements, offering insight into the role of color-octet components in exotic hadron formation.

Speaker: Mr HyeongOck Yun (Yonsei University)

18:18 Quarkonium properties in isospin asymmetric dense \( \Delta \) resonance matter at finite temperature

We present the in-medium masses of the heavy quarkonium (charmonium and bottomonium) states in isospin asymmetric $\Delta$ resonance matter. We have considered nucleons ($n,p$) and delta baryons ($\Delta^{++},\Delta^{+},\Delta^{0}$, and $\Delta^{-}$) as the degree of freedom within the medium. The $J/\psi$ ($\Gamma$) self-energy is evaluated via the $D \bar D$ ($B \bar B$) meson loop, with medium effects incorporated through $D$ ($B$) meson masses computed using the chiral SU(3) hadronic mean field model.
The results are compared with previous studies conducted within nuclear matter and the presence of $\Delta$ resonance baryons in the medium leads to substantial modifications in the effective masses of $J/\psi$ ($\Gamma$) mesons at finite temperature. This may enhance the understanding of upcoming data from heavy-ion collision experiments associated with the FAIR project, such as CBM and PANDA.

Speaker: Manpreet Kaur (Dr. B R Ambedkar National Institute of Technology Jalandhar (144008), Punjab, India)

18:20 Constraints on High-Density Nuclear Symmetry Energy from Flow Observables in Semi-Central 129,124Xe + 124,112Sn Collisions at 100 MeV/nucleon

Understanding the behavior of the nuclear symmetry energy at high baryon densities is crucial for constraining the nuclear equation of state, which plays a central role in both heavy-ion collision physics and astrophysical phenomena such as neutron stars. However, the symmetry energy at supra-saturation densities remains poorly constrained experimentally.

We present an analysis of semi-central 129,124Xe + 124,112Sn collisions at 100 MeV/nucleon, recorded in 1998 at GSI by the INDRA–ALADIN collaboration. Directed and elliptic flow observables were extracted and compared with predictions from the Improved Quantum Molecular Dynamics (ImQMD) transport model employing two Skyrme parameterizations that incorporate different neutron–proton effective mass splitting.

The achieved compression in these collisions, estimated by ImQMD to reach up to ~1.7 ρ₀, allows us to probe the symmetry energy in the supra-saturation regime. The observed agreement and discrepancies between data and model calculations provide sensitivity to effective mass splitting effects and offer new empirical constraints on the symmetry energy at densities above saturation.

Speaker: Seon Ho Nam (Korea University)

18:22 The semi-leptonic decay form factors of $\Xi_b \to \Xi_c \ell^- \bar{\nu}_{\ell}$ in HQET

Heavy-to-heavy semileptonic decays, particularly the bottom-to-charm quark transitions are essential for testing the Standard Model (SM) and extracting the the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements. These decays have been extensively studied using various theoretical approaches. In this work, we investigate the semileptonic decay $\Xi_b \to \Xi_c \ell^- \bar{\nu}_\ell$ (where $\ell = e$, $\tau$) using a phenomenological quark model. We compute the ground state masses of the initial and final baryons to get the wave function. Which is then used to calculate the form factors, including corrections up to order $1/m_Q$ within the framework of Heavy Quark Effective Theory (HQET). The obtained form factors are implemented in the helicity formalism to evaluate the differential decay rates, total decay width and branching ratio.
We compare our results for the form factors at both the maximum and minimum recoil points with previous theoretical studies, finding good agreement. We observe that the form factors depend on the transferred momentum $q^2$ and their magnitude gradually increases with increasing $q^2$. The dominant form factors are $f_1$ and $g_1$ and they also exhibit similar $q^2$ dependencies. Additionally, we calculate the lepton flavour universality (LFU) ratio $R(\Xi_c) \approx 0.3$, which is in agreement with existing theoretical predictions.

Speaker: Kinjal Patel (Government College Daman, VNSGU, Surat, Gujarat, India)

18:24 Probing Baryon Asymmetry via Net-Baryon Transport and Topological Charge Fluctuations in High-Energy Heavy-Ion Collisions

The origin of the observed baryon asymmetry in the Universe remains one of the central puzzles in high-energy physics. Ultra-relativistic heavy-ion collisions at RHIC and the LHC create quark–gluon plasma (QGP) where chiral symmetry is partially restored, and non-perturbative topological transitions (sphalerons, instantons) may induce local CP and baryon number violation. These conditions provide an experimental platform to investigate baryon transport and asymmetry-related phenomena under extreme QCD conditions.

This study examines the rapidity-dependent transport of net baryon number and searches for signatures of anomalous CP-odd domains in the QGP. We propose a novel observable: the Baryon Colour Correlation Ratio (BCCR), defined as the event-by-event covariance of colour charge distributions among constituent quarks normalized to local baryon density gradients. This parameter is sensitive to colour reconnection dynamics and non-perturbative QCD effects during hadronization.

Simulations are performed using event-by-event relativistic viscous hydrodynamics with the MUSIC framework, interfaced with iEBE-VISHNU to include the hadronic afterburner stage. Initial conditions are generated using a Monte Carlo Glauber–IP-Glasma hybrid, spanning √s_{NN} = 7.7–200 GeV (RHIC BES-II) and 5.02 TeV (LHC Pb–Pb). The BICR and higher-order cumulants of net-proton distributions (C_2–C_4) are computed and compared with STAR and ALICE datasets to extract baryon diffusion coefficients and constrain sphaleron transition rates.

This work aims to:
(i) Establish BCCR as a sensitive probe for net-baryon diffusion and anomalous transport in QGP,
(ii) Quantify the energy dependence of baryon chemical potential gradients and their relation to CP-violating fluctuations, and
(iii) Provide theoretical guidance for next-generation heavy-ion experiments at RHIC, LHC, FAIR, and NICA.

The proposed framework integrates baryon number transport analysis with the search for topological CP violation, offering a new diagnostic tool to bridge experimental heavy-ion phenomenology and fundamental baryogenesis models. By introducing BCCR, this study sets a benchmark for future QGP probes and strengthens the experimental case for dedicated baryon-sensitive detector upgrades.

Speaker: Sreenandan K j

18:26 Determination of polarization observables in the reaction γd→n π⁰π⁰ (p)

Investigating the baryon excitation spectrum is essential for understanding the internal dynamics of baryons and quantum chromodynamics (QCD) in the non-perturbative regime. However, it is challenging to identify all baryon resonances and determine their properties due to their short lifetimes, which result in broad and overlapping resonances. The measurement of polarization observables is essential for an unambiguous partial wave analysis. Polarization observables can be measured using a polarized photon beam, a polarized target, or by detecting the polarization of the recoiling nucleon.
A substantial amount of polarized data has been collected from the proton; however, data from the neutron remains sparse, yet it is essential for an isospin decomposition of the amplitudes. Final states involving two mesons are especially valuable for studying sequential decays through intermediate states, offering important insights into baryon dynamics.
The CBELSA/TAPS experiment in Bonn uses linearly or circularly polarized photons and a polarizable (deuterated) butanol target to measure single and double polarization observables across various final states. Its nearly 4π detection coverage is achieved through the combination of the Crystal Barrel and the MiniTAPS calorimeters for photons, as well as additional detector systems for the identification of charged particles.
Preliminary results for polarization observables measured with linearly polarized photons and a polarized deuterated butanol target will be shown for the reaction γd→n π⁰π⁰ (p).
Supported by the DFG (505387544)

Speaker: Nadia Reinartz (Ruhr-Universitaet Bochum (DE))

18:28 Determination of Polarization Observables in $\pi^0 \eta$-Photoproduction off the Neutron

Baryon spectroscopy has the aim to map out the full spectrum of baryon resonances and understand their properties, which requires precise data from both proton and neutron targets. However, most available data to date has been obtained using proton targets. Since some resonances may couple more strongly to neutrons than to protons, neutron-target experiments are essential for a complete understanding of the nucleon excitation spectrum. Final states with two mesons allow the investigation of sequential decays via intermediate states, providing important information about baryon dynamics. Polarization observables are indispensable for an unambiguous partial wave analysis used to extract the broad and overlapping resonances and their properties from the data. The use of polarized beams and targets allows for the determination of asymmetries that are sensitive to interference terms between different resonant and non-resonant amplitudes. At the CBELSA/TAPS experiment in Bonn, measurements are carried out using a polarized photon beam and various targets, including a deuterated butanol target with polarizable neutrons. However, since the neutrons which can be polarized are bound in deuterons, sophisticated analysis methods are required to suppress background contributions and to account for the Fermi motion of deuteron-bound neutrons. In this contribution, preliminary results for polarization observables in the reaction $\gamma n (p) \rightarrow n \pi^0 \eta (p)$ will be presented. (Supported by DFG: 505387544)

Speaker: Mr Leoniedas Reschke (Justus-Liebig-Universitaet Giessen (DE))

18:30 Exploring hadronic rescattering effects on resonance productions in pp and p--Pb collisions with PYTHIA8 in ALICE acceptance

In relativistic heavy-ion collisions, the quark-gluon plasma is created, and as the medium cools down, the system transitions into a hadronic phase. While such interactions are well established for large systems, such as Pb-Pb collisions, their relevance in smaller collision systems remains unclear. Therefore, we analyse pp collisions at $\sqrt{s}=13$ TeV and p-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV events using PYTHIA8 at the ALICE acceptance, at midrapidity ($|y|<0.5$). The observable is the yield ratio of short-lived resonances to their stable counterparts as a function of $p_\mathrm{T}$: $\rho(770)^0/\pi^\pm$, $\mathrm{K^*(892)^0/K^\pm}$, and $\mathrm{\phi(1020)/K^\pm}$. Ratios are reported in five (pp) and six (p-Pb) multiplicity classes, referenced to pp 60-100\%. Turning hadronic rescattering on yields stronger suppression at low $p_\mathrm{T}$($<2$ GeV/$c$); however, a visible suppression persists even with rescattering off. To isolate rescattering, we form double ratios (on/off), then integrate over $0<p_\mathrm{T}<6.0$ GeV/$c$. The normalised double ratios decrease with increasing multiplicity, similarly in pp and p-Pb. From the integrated ratios, the lower limit of the hadronic phase lifetime increases with multiplicity in both systems, with a notable pp and p-Pb discrepancy. This poster aims to study hadronic phase effects in small systems via resonance-to-stable yield ratios and rescattering-sensitive double ratios, and to quantify the multiplicity dependence of the hadronic phase lifetime in pp and p-Pb collisions.

Speaker: Su-Jeong Ji (Pusan National University (KR))

18:32 Study of multiplicity-dependent resonance productions in small systems in the EPOS4

Recently, ALICE observed that the production of the short-lived resonance $K^*(892)$ is reduced in high multiplicity pp collisions compared to its ground state $K^\pm$, while long-lived resonances like $\phi(1020)$ exhibit no multiplicity dependence. This reduction is attributed to the decay product undergoing hadronic interactions within the hadron gas phase. This phenomenon, termed rescattering, is extensively studied in Pb-Pb collisions. However, recent results indicate the possible existence of hadronic interactions, such as the rescattering effect, even in small systems such as pp. Therefore, it becomes crucial to consistently predict the multiplicity-dependent suppression of resonance production across various collision systems, including small systems. Theoretical models such as EPOS have successfully elucidated this phenomenon in Pb-Pb collisions, particularly when coupled with UrQMD, which incorporates hadronic interactions. Thus, this presentation aims to showcase the reproducibility of ALICE measurements of $\phi(1020)$ and $K^*(892)$ in pp collisions, employing the EPOS4 and UrQMD models. Additionally, it presents the results of other resonances, $\rho(770)^0$, $\Delta^{++}(1232)$, $\Sigma^{\pm}(1385)$, $\Lambda(1520)$ and $\Xi(1530)^0$. These findings enhance our comprehension of hadronic interactions within small systems, thereby offering valuable insights into the hadronic phase.

Speaker: Hyunji Lim (Pusan National University (KR))

Wednesday 12 November

09:00 → 10:40 Plenary: Plenary 7

09:00 Studies of vector mesons in nuclei in proton-nucleus collisions (J-PARC E16 and E88)

J-PARC E16 and E88 experiments aim to study chiral-symmetry restoration of vector mesons by measuring their mass in $e^+e^-$ and $K^+K^-$ decays in proton-nucleus collisions. In the previous KEK-E325 experiment, the mass reduction of $\phi$ was observed at low velocity in p+Cu collisions in its $e^+e^-$ decay. E16 will measure several thousand $\phi \rightarrow e^{+}e^{-}$ events in p+C and p+Cu in the first physics run. E88 will collect about one million $\phi \rightarrow K^{+}K^{-}$ decay events in p+C, p+Cu, and p+Pb collisions. We will study the mass dependence on the momentum (dispersion relation) complementarily. The $\bar{s}s$ condensate at finite density will be evaluated quantitatively by extrapolating the $\phi$ mass shift to zero momentum. E88 also aims to measure the dependence of the dispersion relation on $\phi$ polarities. The $\phi$ polarity can be distinguished with a $K^\pm$ decay angles at E88.
E16 and E88 share the E16 spectrometer. Electron identification performance with HBD (Hadron-Blind Detector) and LG (Lead-Glass calorimeter), has been evaluated in the E16 commissioning runs. In the trigger-study run in 2024, $\omega$ and $\phi$ peaks in the $e^+e^-$ invariant mass have been observed. Particle identification detectors for E88, MRPC (Multi-gap Resistive Plate Chamber), SC (Start-timing Counter), and AC (Aerogel Cherenkov counter) have been developed to be installed at forward angles in the J-PARC E16 spectrometer for Kaon identification.
In this presentation, we will show the physics goals, the experimental setups, as well as the preparation status, preliminary results, and the schedules of both experiments.

Speaker: Dr Hiroyuki Sako (Japan Atomic Energy Agency)

09:25 Hadrons in nuclear matter, theory and simulations

In this talk, I will present an overview of recent investigations
into the behavior of hadrons in nuclear matter, with a particular
focus on vector and axial-vector mesons. These mesons serve as especially
sensitive probes for exploring in-medium modifications and are central
to several ongoing experimental programs, including the J-PARC E16
and E88 experiments.
I will begin by reviewing theoretical developments in this area,
encompassing both hadronic effective field theory approaches and
frameworks that incorporate explicit quark and gluon degrees of freedom.
Subsequently, I will discuss recent efforts to bridge theory and
experiment through numerical simulations of the relevant reactions,
employing relativistic transport theory to model the dynamics observed
in experimental settings.

Speaker: Philipp Gubler (JAEA)

09:50 The nature of baryon resonances in QCD

We are still far from understanding how QCD works. Baryon excited states have an important role to play in resolving the problem. In particular, we need to identify whether some states are better viewed as dynamically generated, rather than as three valence quark states. This issue is currently surrounded by some confusion. We aim to remove some of that confusion, as well as citing examples of both kinds of states.

Speaker: Anthony Thomas

10:15 Probing the Hot QCD Medium via Thermal Dileptons in Heavy Ion Collisions

Thermal dileptons, emitted throughout the space-time evolution of the hot QCD medium in relativistic heavy-ion collisions, interact weakly with surrounding partonic and hadronic matter. This minimal interaction makes them as idea penetrating probes, providing direct insights into the medium’s properties. Their invariant mass spectra, unaffected by blue-shift effects from the medium’s rapid collective expansion, offer a direct measure of the emitting source’s temperature. Furthermore, dileptons produced at distinct evolutionary stages dominate specific mass regions, enabling differential access to the medium’s temperature evolution. In this talk, we will review recent advancements in measuring thermal dilepton production and discuss their implications for understanding the thermodynamic properties of the quark-gluon plasma in heavy-ion collisions.

Speaker: Prof. Zaochen Ye (South China Normal University)

10:40 → 11:10 Coffee break

11:10 → 12:25 Plenary: Plenary 8

11:10 Exotic Hadrons with Two Strange Quarks

This presentation will share preliminary results from our search for the H-dibaryon near the $\Xi^-p$ and $\Lambda\Lambda$ mass thresholds using the E42 detector. The E42 has collected two orders of magnitude more statistics than we have ever achieved before, enabling us to provide a definitive answer regarding the existence of the H-dibaryon.

Furthermore, we will introduce a new experiment (E104) focused on elucidating the nature of double phi production in $\bar{p}p$ reactions near the threshold. While this process is anticipated to be highly suppressed, with a predicted cross-section of about 10 nb, a previous JETSET experiment revealed an unexpectedly large cross-section of a few
$\mu$b. We have proposed a new measurement of this production process from the threshold up to 2.14 GeV.

This presentation will detail these two experiments aimed at exploring exotic hadronic systems that contain two strange quarks.

Speaker: Prof. Jung Keun Ahn (Korea University)

11:35 Antikaon-Nuclear Bound Systems at J-PARC - from Lambda(1405) to KbarNNN and Beyond

The strongly attractive antikaon–nucleon ($\bar K N$) interaction in the $I=0$ channel has led to the widespread interpretation of the $\Lambda(1405)$ resonance as a $\bar K N$ bound state, motivating the study of exotic antikaon-nuclear bound systems known as kaonic nuclei. At J-PARC, we have carried out a systematic experimental program to search for and study these systems, extending from the elementary $\bar K N$ interaction to few-body nuclei.

In the J-PARC E15 experiment, we searched for the simplest kaonic nucleus, $\bar K NN$, via the $^3\mathrm{He}(K^-, n)$ reaction, detecting the $\Lambda$ and proton from its decay and identifying the neutron through missing-mass analysis. The observation of a distinct peak below the $K^-pp$ mass threshold provided strong evidence for its formation. To better understand the fundamental interaction governing such states, we also conducted the E31 experiment, yielding a key input by precisely determining the $\Lambda(1405)$ line shape through the $d(K^-,n)\pi\Sigma$ reaction.

Building on these successes, we are currently upgrading our spectrometer for the newly approved E80 experiment, which will extend our investigation to the $\bar K NNN$ system and heavier $\bar K$–nuclear systems. This systematic approach, exploring the mass-number dependence of kaonic nuclei, is expected to provide definitive insights into the nature of kaonic nuclei. We summarize the key results from E15 and E31, and outline future prospects of this systematic study, beginning with E80.

Speaker: fuminori sakuma (RIKEN)

12:00 Hyperon Physics at BESIII

Using the large $J/\psi$ and $\psi(3686)$ datasets from the BESIII experiment, recent studies have revealed significant transverse polarization in hyperon-antihyperon pairs such as $\Lambda\bar{\Lambda}$, $\Sigma\bar{\Sigma}$, $\Xi\bar{\Xi}$, and $\Omega^-\bar{\Omega}^+$, enabling the first model-independent determination of the $\Omega^-$ spin. Non-zero polarization allows independent measurements of hyperon and antihyperon decay parameters, offering precise tests of direct CP violation.

BESIII also enables a novel method to probe hyperon electric dipole moments (EDMs) via entangled pairs in $J/\psi$ decays. This approach could reach sensitivities of $10^{-19} \, \text{e}\cdot\text{cm}$ for $\Lambda$, $\Sigma^+$, $\Xi^-$, and $\Xi^0$, surpassing previous limits by several orders of magnitude. These results provide powerful tests for new physics beyond the Standard Model, with further improvements expected at the STCF experiment.

Speaker: Jianyu Zhang (University of Chinese Academy of Sciences (CN))

13:00 → 18:00 Excursion

18:30 → 20:30 IAC meeting

Thursday 13 November

09:00 → 10:40 Parallel Session A: Spectroscopy of hadrons 2

09:00 Quark-model search for compact strange-hidden-charm pentaquark states

We investigate the structure of a possible compact pentaquark state, $P_{c\bar{c}s}(4338)$, with quantum numbers $J^P = 1/2^-$, recently reported by the LHCb collaboration. A realistic constituent quark model is employed to explore the existence of bound and/or resonance five-quark configurations, focusing on hidden-charm systems with strangeness. The model Hamiltonian used in this study accurately reproduces the spectra of low-lying charmed and strange hadrons, serving as a solid foundation for multi-quark calculations.

To solve the five-body Schrödinger equation, we utilize the Gaussian Expansion Method, incorporating all relevant baryon–meson threshold channels explicitly to account for coupled-channel dynamics. In addition, the real-scaling (stabilization) method is applied to distinguish genuine resonance states from continuum states.

Particular attention is paid to the role of hidden-color configurations, especially the $(uds)_8$–$(c\bar{c})_8$ color-octet components, in the formation and stabilization of the pentaquark state. We present our findings on the nature of the $P_{c\bar{c}s}(4338)$, its dominant configuration, and the implications for the structure of exotic baryons with hidden charm.

Speaker: Makoto Oka (RIKEN Nishina Center)

09:20 A model study of hidden-, double-, and single-charm pentaquark states

The properties of the near-threshold hidden-charm pentaquark-like states, Pc(4312), Pc(4440), Pc(4457), and so on, are widely discussed in the baryon-meson molecule picture. According to the consistency between spectrum and decay width ratios, we find that one may also interpret them as compact pentaquarks. This requires that the J^P assignment for Pc(4312) to be 3/2^- which is different from the assignment in the molecule picture. We here discuss the implications of this J^P for spectra of doubly and singly charmed pentaquark states. We find stable ground states such as $I(J^P)=0(1/2^-)$ $ccud\bar{s}$ and $I(J^P)=1/2(1/2^-)$ $cnns\bar{n}$ (n=u,d).

Speaker: Yan-Rui Liu

09:35 Light hybrid mesons in QCD sum rules

The existence of hybrid mesons is one of the most distinctive predictions of QCD. In the past several decades, there have been lots of efforts on searching for hybrid mesons in both experimental and theoretical aspects. In this talk, I will introduce our recent calculations of the hybrid meson masses based on the method of QCD sum rules, especially focus on those with exotic quantum numbers.

Speaker: Wei Chen

09:50 Spectroscopy of singly heavy flavor baryons

With the efforts of every energy physics Collaborations, more and more singly heavy flavor baryons were observed, which provide a good platform to study the properties of these baryons. In this report, we present the mass spectra, decay behaviors, symmetries, and hadron loop effects of the singly heavy flavor baryons. We hope more singly heavy flavor baryons could be observed in experiments.

Speaker: Si-Qiang Luo (Lanzhou University)

10:05 Resolving the flavor-dependency puzzle with quark three-body forces

For many years, it has been known that in all quark models, the meson and baryon spectra cannot be simultaneously reproduced using a single set of model parameters. Recently, we have found that this puzzle can be resolved by introducing a quark three-body force. This approach is analogous to that in nuclear physics, where it is recognized that fitting the binding energy of the triton or nuclei with $A>2$ requires a three-body nuclear force. We start with an introduction and then discuss the lack of success in simultaneously describing mesons and baryons unless one introduces ad hoc flavor-dependent parameters to eliminate the otherwise residual flavor dependence: masses for states dominated by light quarks are invariably overestimated, while those dominated by heavy quarks are systematically less overestimated or even underestimated. We show this "flavor dependency puzzle" is resolved by introducing a natural short-ranged quark three-body force with color-spin dependence inspired by the nuclear three-body force. We explain the methods for a comprehensive $S$-, $P$-, and $D$-wave Gaussian Expansion Method (GEM), to achieve an unprecedented baryon root-mean-square error (RMSE; $\sigma$) of $\sim3$ MeV, fully reproducing experimental masses across the light, strange, and heavy sectors. This confirms that a genuine, short-range three-body interaction is both necessary and sufficient to unify hadron spectroscopy, paving the way to a universal quark model of mesons, baryons, and exotic multiquark states.

Speaker: Jongheon Baek (Yonsei University)

10:20 The Electron-Ion Collider as A Prospective Facility for Pentaquark Measurements

The Electron-Ion Collider (EIC) is a cutting-edge facility which will offer us the valuable chance to study the nature of heavy pentaquarks due to its high value of center of mass energy, luminosity and spin polarization abilities. In our work, we compute the electroproduction of P_c (4312) for possible quantum numbers of spin-parity by applying the vector meson dominance hypothesis which is constrained by the result of LHCb and GlueX experiments. The calculation shows that the production yield of P_c (4312) are enhanced at low collision energy if the spin assignment is 1/2 or 3/2, whereas the spin 5/2 production yield is enhanced at high collision energy. We also propose the double spin asymmetry and the decay angle kinematic of J/ψ can aid in determining the spin-parity of P_c (4312).

Speaker: In Woo Park (Yonsei University, South Korea)

09:00 → 10:40 Parallel Session B: Hadron-hadron Interactions 2

09:00 Two-Pion Exchange Paradigm in Hadron-Hadron Interactions from Lattice QCD

In the nuclear force between nucleons,the long-range part of the interaction at distance $𝑟 ∼ (𝑚_𝜋)^{-1}$ is dominated by the one-pion exchange potential (OPEP), originally proposed by Yukawa. At intermediate distances, $𝑟 ∼ (2𝑚_𝜋)^{−1}$, the leading contribution arises from the two-pion exchange potential (TPEP).

If both nucleons in the NN system are replaced by flavor-singlet hadrons, OPEP is no longer allowed. In this case, the longest-range interaction must arise from TPEP. A characteristic example is the interaction between two heavy quarkonia, such as bottomonium-bottomonium or charmonium-charmonium systems. At long distances, the gluons surrounding each $\bar{𝑄}𝑄$ pair couple to flavor-singlet two-pion states, which can be exchanged between the dipoles to generate the TPEP. This type of interaction was first investigated by Peskin and Bhanot, and was later clarified using dispersion relations and chiral EFT.

If only one of the nucleons in the NN system is replace by a flavor-singlet hadron, it is an intermediate situation between the cases discussed above. Since the flavor-singlet hadron is involved, OPEP is still inhibited and the possible long-range interaction should come from TPEP. By using lattice QCD simulations with (2+1)-flavor configurations on a lattice volume $L = (8.1 {\rm fm})^3$ with $m_\pi \simeq 146$ MeV together with the charm quark at its physical mass implemented by relativistic quark action, we have studied $N$-$\phi$, $N$-$J/\psi$ and $N$-$\eta_c$ interactions and found the eviidence of the universal feature of TPEP at long distances [1].

I will report the current status of this TPEP paradigm on the basis of the latest lattice QCD simulations.

[1] T. Hatsuda, "Hadron-Hadron Interactions from Lattice QCD: Theory meets Experiments", https://arxiv.org/abs/2507.08359

Speaker: Tetsuo Hatsuda (RIKEN iTHEMS)

09:20 Extracting Hermitian and regular hadron potentials from HAL QCD wave functions

The HAL QCD method has gained popularity for deriving hadron interactions from lattice QCD simulations. However, it has faced criticism for its systemic uncertainties, particularly regarding the derivative expansion method used to extract potentials from Nambu-Bethe-Salpeter (NBS) wave functions. In this talk, I will introduce a novel approach to extracting hadron potentials from HAL QCD wave functions, grounded in the principles of effective field theory. Compared to the derivative expansion method, this new approach ensures the Hermiticity of the potential and avoids issues with singular potentials. Additionally, it provides a robust framework for higher-order corrections and facilitates the consistent extraction of three-body forces in the future. I will demonstrate the efficacy of this method using a realistic nucleon force as an example.

Speaker: Lu Meng

09:35 Meson-baryon and baryon-baryon interactions in manifestly Lorentz-invariant ChEFT

We investigated meson-baryon and baryon-baryon scatterings using time-ordered perturbation theory (TOPT) based on a manifestly Lorentz-invariant formulation of chiral effective field theory. This unified framework defines the effective potentials as sums of two-particle irreducible contributions from time-ordered diagrams, and obtains the renormalized scattering amplitudes by solving the integral equations, which are derived self-consistently in TOPT.

We successfully applied this formalism to pion-nucleon scattering at leading order (LO) and meson-baryon scattering in the S=-1 sector. By solving coupled-channel integral equations, we obtained the two-pole structure of Λ(1405). Our parameter-free prediction of pole positions is in agreement with the BaSc lattice results.

For baryon-baryon scattering, we demonstrated that the nucleon-nucleon potential is perturbatively renormalizable at LO, with unique solutions in all partial waves. We extended to Lambda-nucleon scattering and addressed renormalization issues. Through evaluating the two-pion exchange contribution at one-loop level, we formulated the NN interaction up to next-to-next-to-leading order (NNLO). Good agreement with phase shifts and deuteron properties is achieved by treating the full NNLO potential non-perturbatively.

Speaker: Xiu-Lei Ren (Shandong University)

09:50 One-pion exchange potential in a strong magnetic field

Extremely strong magnetic fields are generated in non-central relativistic heavy-ion collisions (RHIC/LHC) and exist in magnetars, driving studies of hadrons and QCD matter under intense fields. Most work has addressed single-particle properties (e.g., masses) and mean-field descriptions in background fields.

Beyond such one-body treatments, a key question is how hadron–hadron interactions are modified. Recent studies have begun to explore effects on the nuclear force, yet a detailed account of how the standard one-pion exchange potential (OPEP)—in particular its spin- and isospin-dependent structure—changes in strong fields remains missing [1].

We derive the OPEP in a strong, uniform magnetic field within chiral perturbation theory for nonrelativistic nucleons. We define a OPEP via the charged-pion Green’s function in the magnetic field and discuss implications for the deuteron: the range of the force mediated by charged-pion exchange shortens both parallel and transverse to the field, and we estimate the deuteron energy shift at first order perturbation theory.

[1]F. L. Braghin, M. Loewe, and C. Villavicencio, Phys. Rev. D 109, 034014 (2024)

Speaker: Daiki Miura (Niigata University)

10:05 Probing Nucleon-$\Omega_{\rm ccc}$ Interaction via Lattice QCD at Physical Quark Masses

We study the S-wave interactions between the nucleon ($N$) and the triply charmed Omega baryon ($\Omega_{\mathrm{ccc}}$) using (2+1)-flavor lattice QCD with a physical pion mass ($m_\pi \simeq 137.1$ MeV) on a lattice volume $\simeq (8.1~\mathrm{fm})^3$.
The charm quark is implemented with a relativistic heavy-quark action at its physical mass.
Employing the time-dependent HAL QCD method, the $N$-$\Omega_{\mathrm{ccc}}$ potentials in the spin-1 ($^3\mathrm{S}_1$) and spin-2 ($^5\mathrm{S}_2$) channels are extracted.
In both channels, overall attraction is found with the scattering parameters,
$a_0 = 0.56(0.13)\left(^{+0.26}_{-0.03}\right)$ fm and $r_{\mathrm{eff}} = 1.60(0.05)\left(^{+0.04}_{-0.12}\right)$ fm for the $^3\mathrm{S}_1$ channel, and
$a_0 = 0.38(0.12)\left(^{+0.25}_{-0.00}\right)$ fm and $r_{\mathrm{eff}} = 2.04(0.10)\left(^{+0.03}_{-0.22}\right)$ fm for the $^5\mathrm{S}_2$ channel,
indicating the absence of a dibaryon bound state.
The extracted potentials are further decomposed into spin-independent and spin-dependent components.
The spin-independent potential is a dominant component and features a short-range attractive core and a long-range attractive tail, while the spin-dependent potential shows short-range attraction (repulsion) in the spin-1 (spin-2) channel.
Qualitative comparisons with previous studies of the $N$-$J/\psi$ and $N$-$\Omega_{\rm{sss}}$ systems at $m_\pi \simeq 146$ MeV are provided, emphasizing the role of heavy-hadron chromo-polarizability arising from soft-gluon exchange between the nucleon and flavor-singlet hadrons.
The charm quark mass dependence of the $N$-$\Omega_{\rm ccc}$ potential is investigated as well.

Speaker: Liang Zhang (Shanghai Institute of Applied Physics, Chinese Academy of Sciences)

10:20 Understanding the Structure of Doubly-Heavy Tetraquarks based on the Diquark Model

We investigate the $T_{cc}$ tetraquark, treating it as a bound state of a heavy diquark and a light anti-diquark. Using the Silvestre–Brac potential and solving the Schrödinger equation via the Gaussian Expansion Method, we find that the excitation energy between the heavy-diquark and light anti-diquark is unexpectedly larger than that between the two light quarks within the anti-diquark — contrary to the naive expectation where the former is smaller than the latter. We trace this inversion of the mass hierarchy to the centrifugal force acting on the light degree of freedom. Applying the same framework to other systems ($T_{bb}, \Lambda_b, \Lambda_c$) yields qualitatively identical behavior, demonstrating the robustness of the mechanism. These results provide new insights into diquark dynamics and the mass structure of exotic hadrons.

Speaker: Maximilian Weber

09:00 → 10:40 Parallel Session C: Hadrons at finite density & temperature 2

09:00 Astrophysical constraints on dense matter EoS

The observations of the neutron star binary GW170817 detected by gravitational waves and the neutron star observed by NICER provide astronomical constraints on dense matter equation of state (EoS). We anticipate that future astronomical observations will provide more precise constraints on dense matter EoS, and in this presentation, we will discuss the related topics in general.

Speaker: Young-Min Kim (Korea Astronomy and Space Science Institute (KASI))

09:20 Connecting dilaton thermal fluctuation with the Polyakov loop at finite temperature

Understanding the character of the deconfinement phase transition in quantum chromodynamics (QCD) is one of the fundamental challenges in particle physics. On the one hand, for a pure $\mathrm{SU}(N_{\mathrm{c}})$ system at finite temperature, the expectation value of the Polyakov loop $\langle\Phi\rangle$ is the order parameter of the deconfinement phase transition and on the other hand, the scale symmetry broken by the trace anomaly effect in QCD vacuum is anticipated to restore at high temperature. In this work, inspired by the fact that the dilaton field $\chi$ is introduced by the matching of the trace anomaly and both the Polyakov loop and the dilaton field depend on gluonic configurations, we construct a possible relationship between the Polyakov loop and the dilaton field and derive a formula for $\langle\Phi\rangle$ as a function of temperature. Firstly, we investigate the scale transformation of the Polyakov loop based on the scale transformation of temperature which is derived on the basis of the scale covariance of Liouville equation. Then, we expand the thermal fluctuation of the dilaton field as a power series with respect to the Polyakov loop and retain $\mathbb{Z}_{N_{\mathrm{c}}}$-symmetric terms like $\Phi^{N_{\mathrm{c}}}+(\Phi^{N_{\mathrm{c}}})^{*}$ but exclude all $\mathrm{U(1)}$-invariant terms such as $\Phi\Phi^{*}, (\Phi\Phi^{*})^{2}, \cdots$ which are also $\mathbb{Z}_{N_{\mathrm{c}}}$-invariant. For the coefficients in the power series, they are all proportional to the temperature $T$ due to the scale transformation rules of $T$, $\Phi$ and $\chi$. We next focus on the next-to-leading order (NLO) and the next-to-next-to-leading order (NNLO) of the power series and derive the formulae of $\langle\Phi\rangle_{\mathrm{NLO}}$ and $\langle\Phi\rangle_{\mathrm{NNLO}}$ respectively by minimizing the effective potential of the dilaton field, i.e., the Coleman—Weinberg-type potential. Finally, we obtain the values of the parameters in the formulae by globally fitting the Lattice QCD (LQCD) data of $\langle\Phi\rangle$ and we find that our formulae are not only in good agreement with LQCD but also can describe the large-$N_{\mathrm{c}}$ behavior of $\langle\Phi\rangle$ when we compare the results predicted by our formulae with those of 4-8PLM model in other researchers’ work. In conclusion, our work provide a possible relationship between the scale restoration and the deconfinement phase transition and a possible hint that one may comprehend the confinement phenomenon starting from investigating the trace anomaly.

Speaker: Dr Bing-Kai Sheng (School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, UCAS)

09:35 Mass modifications of singly heavy baryons in hot medium with chiral symmetry restoration

Masses of the singly heavy baryons (SHBs), composed of a heavy quark and a light diquark, are studied from the viewpoints of heavy-quark spin symmetry (HQSS) and chiral-symmetry restoration at finite temperature. We consider the light diquarks with spin-parity $J^P=0^\pm$ and $J^P=1^\pm$. Medium corrections to the SHBs are provided through the diquarks whereas the heavy quark is simply regarded as a spectator. The chiral dynamics of the diquark are described by the Nambu-Jona-Lasinio (NJL) model having (pseudo)scalar-type and (axial)vector-type four-point interactions and the six-point ones responsible for the $U(1)$ axial anomaly. As a result, we find that mass degeneracies of the certain SHBs carrying opposite parities are realized at high temperature due to the chiral restoration. We also discuss consequence of the anomaly effects and phenomenological impact of the mass degeneracies.

Speaker: Daiki Suenaga (KMI, Nagoya University)

09:50 Addressing the sign-problem in Euclidean path integrals with radial basis function neural networks

Interacting quantum field theories at finite densities pose significant numerical and conceptual challenges, even with modern computational capabilities. In this talk, I propose a new method, based on an expansion of Euclidean path integrals using radial basis function neural networks, which allows the calculation of observables at finite densities and overcomes the sign problem in a numerically very efficient manner. The method is applied to the interacting complex scalar field theory at finite chemical potentials in 3+1 dimensions, which exhibits both the sign problem and the silver blaze phenomenon.

Speaker: Gabor Balassa

10:05 Numerical exploration of dense QCD in (1+1) dimensions using Hamiltonian formalism

We study one-flavor $\mathrm{SU}(2)$ and $\mathrm{SU}(3)$ lattice QCD in $1+1$ dimensions at zero temperature and finite density using matrix product states and the density matrix renormalization group. We compute physical observables such as the equation of state, chiral condensate, and quark distribution function as functions of the baryon number density. As a physical implication, we discuss the inhomogeneous phase at nonzero baryon density, where the chiral condensate is inhomogeneous, and baryons form a crystal. We also discuss how the dynamical degrees of freedom change from hadrons to quarks through the formation of quark Fermi seas.

Speaker: Kentaro Nishimura

10:20 Nuclear matter properties and neutron star structures from an extended linear sigma model

Unlike the widely used Walecka-type models for studying nuclear matter properties and neutron star structures, we extended the linear sigma model, originally developed by Schechter and his colleagues, to the baryonic sector to explore dense nucleon systems. This extended framework is termed the baryonic extended linear sigma model (bELSM).

The bELSM incorporates 2-quark and 4-quark configurations to address the P-wave problem of the lowest-lying scalar meson, sigma. Beyond its original purpose, the model offers a systematic way to include delta mesons and hyperons, guided by the chiral symmetry pattern. By employing the relativistic mean field theory, we introduced density effects, revealing a plateau-like behavior of symmetry energy at intermediate densities. This outcome aligns with the FSU-delta model results, where delta mesons were included to resolve inconsistencies between the properties of $^{208}$Pb and the tidal deformation of neutron stars observed in GW170817. Notably, the delta meson couplings, including $g_{\delta NN}$ and its interactions with sigma, differ significantly from those in Walecka-type models that include delta meson dynamics.

An intriguing discovery is that, when incorporating all possible leading-order terms, the squared sound velocity approaches $1/3$ at high densities, following parameters determined by empirical data. As the bELSM encodes the chiral symmetry pattern of QCD, it offers valuable insights into how QCD phenomena impact macroscopic observations.

Additionally, I aim to present some results for the SU(3) case, where explicit symmetry breaking from quark mass terms will play a key role in deciding high density behaviors of neutron star EOS, and this may provide us a new insight into the relationship between microscopic symmetries and macroscopic phenomena.

Speaker: Yao Ma (Nanjing University)

09:00 → 10:40 Parallel Session D: Recent developments in QCD 2

09:00 Tackling the Inverse Problem in PDFs from lattice QCD

The upcoming Electron Ion Collider promises unprecedented access to the internal structure of hadrons and nuclei encoded in parton distribution functions (PDFs). With the development of effective theory approaches, such as quasi- and pseduo-PDFs, first principles Lattice QCD simulations take aim at precision computation PDFs, offering complementary insight.
The extraction of physical PDFs from lattice simulations however requires the solution of an ill-posed inverse problem, which calls for the use of modern statistical inference methods. In this talk I will discuss how the inverse problem arises in the study of PDFs and survey state-of-the-art methods to tackle this computational challenge.

Speaker: Prof. Alexander Rothkopf (Korea University)

09:20 Baryon Spectroscopy for Precision Predictions in 2+1-Flavor Lattice QCD

We present results on baryon spectroscopy in thirteen 2+1-flavor lattice QCD using Wilson–clover fermion ensembles generated by the JLab/ W\&M/LANL/MIT/Marseille collaborations. From the baryon spectra we determine, we track the chiral and lattice-spacing dependence, enabling a precise determination of the physical scale. Taken together, these results suggest a systematic strategy for investigating baryonic observables on the lattice with controlled uncertainties. In addition, we report supporting results for pseudoscalar decay constants, the ratio $f_K/f_\pi$, gradient-flow scales $t_0$ and $w_0$, and the topological susceptibility. Our study highlights how baryon observables can serve as both a precision probe of QCD and a benchmark for future lattice calculations of hadronic structure.

Speaker: Jun-Sik Yoo

09:35 Resummation of the Bjorken Sum Rule in Holomorphic QCD

We perform an evaluation of the polarised Bjorken sum rule (BSR) $\overline{\Gamma}^{p-n}_1(Q^2)$ with truncated Operator Product Expansion (OPE) up to the $D=4$ term [1]. Using the knowledge of the renormalon structure of the BSR, the leading-twist term of dimension $D=0$ is evaluated using a renormalon-based resummation [2], in this case [1] with two variants of previously developed holomorphic QCD couplings [$a(Q^2) \mapsto {\mathcal A}(Q^2)$] which have no Landau singularities and thus require, in contrast to the perturbative QCD (pQCD) case (explored in our previous work [3]), no regularisation of the resummation formula. The $D=2$ and $D=4$ terms are then included in the OPE of the inelastic BSR, and fits are performed to the available experimental data.

With this approach, the $Q^2$-interval in the fit can be significantly enhanced and extended to lower $Q^2$-values and the extracted residue parameter values become more stable.

[1] C. Ayala, C. Castro-Arriaza and G. Cvetic, Nucl. Phys. B 1007, 116668 (2024).
[2] G.Cvetic, Phys. Rev. D 99 no.1, 014028 (2019).
[3] C. Ayala, C. Castro-Arriaza and G. Cvetic,
Phys. Lett. B 848, 138386 (2024).

Speaker: Camilo Castro Arriaza (Nagoya University)

09:50 Different scenarios of dynamical chiral symmetry breaking in the interacting instanton liquid model via flavor symmetry breaking

We examine the transitional behavior of dynamical chiral symmetry breaking in the interacting instanton liquid model (IILM) with $N_f=2$ and $N_f=2+1$ flavors. In our previous study, we demonstrated that in the IILM with the dynamical quarks of $N_f=3$, chiral symmetry breaking is driven in an anomaly-assisted manner. In contrast, our quenched calculation of the IILM revealed a typical scenario of dynamical chiral symmetry breaking, as seen in models like the Nambu--Jona-Lasinio model. The quenched calculation corresponds to the system in the heavy quark mass limit for three-flavor quarks. This motivates the investigation of transitional behaviors in systems with intermediate quark flavors, such as $N_f=2$ and $N_f=2+1$, where varying quark masses could significantly affect chiral symmetry breaking patterns. We present numerical results obtained from simulations of the canonical IILM with dynamical light quarks.

Speaker: Yamato Suda

10:05 Monte Carlo Simulation for the LHC Experiments at CERN: A Comprehensive Overview

This overview of the Monte Carlo (MC) simulation process at the four main experiments - ATLAS, CMS, ALICE, and LHCb - at the Large Hadron Collider (LHC) is provided in this talk. Given the complexity and noise of proton-proton collisions, simulated samples are essential for understanding and interpreting the experimental results, enabling precise measurements and searches for new physics. The general simulation workflow consists of three main stages: event generation, detector simulation, and digitization. This process is explored in all four experiments, identifying both shared methodologies and experiment-specific adaptations. Key software tools such as PYTHIA for event generation, GEANT4 for particle tracking, and dedicated experiment frameworks are discussed. In addition to highlighting the technical process, the presentation also addresses computational resources and the time required for these simulations. Looking ahead, the upcoming High-Luminosity LHC (HL-LHC) will amplify these challenges, necessitating improvements in the efficiency and scalability of simulation tools. This presentation aims to offer a structured understanding of LHC data simulation and its future directions.

Speaker: Marija Rapseviciute (Vilnius University (LT))

10:40 → 11:10 Coffee break

11:10 → 12:35 Parallel Session A: Spectroscopy of hadrons 3

11:10 Hidden-charm pentaquark state with strangeness S=-3 in coupled-channel approach

We study hidden-charm pentaquark states $P_{c\bar{c}sss}$ using a fully off-mass-shell coupled-channel formalism with four heavy meson-heavy baryon channels to generate the scattering matrix. The kernel amplitudes are constructed from one-meson exchange diagrams based on an effective Lagrangian respecting heavy quark spin symmetry and hidden-local symmetry. Our calculations reveal two dynamically generated resonances with spin-parity $J^P = 1/2^-$. To explore experimental signatures, we study transitions to the $J/\psi\Omega$ final state and find that the first resonance appears clearly in the $J/\psi\Omega$ invariant mass spectrum. These results can guide future experimental searches.

Speaker: Samson Clymton (Asia Pacific Center for Theoretical Physics (APCTP))

11:25 Structure of the $X(3915)$ within a quark model analysis

We study the structure of the $X(3915)$ meson by calculating its mass and production.
Solving for the color–spin configuration corresponding to the expected quantum numbers of the $X(3915)$, we find that the lowest-energy state corresponds to a well-separated $D^+_s$ $D^-_s$​ configuration.
To discuss the internal structure of the $X(3915)$, which contains two strange quarks and has total spin zero, we analyze the color-spin interactions and mixing between different color states, since the color-spin interaction energy provides the dominant attractive contribution in a tetraquark configuration.
Our analysis suggests that, while the state is unlikely to be a compact configuration, it could possibly be a well-separated molecular configuration arising from a meson exchange type interaction.
We then briefly present the results from the coalescence model analysis on the possible structures of the $X(3915)$, including charmonium, tetraquark, and hadronic molecule states.

Speaker: Sungsik Noh (Kangwon National University)

11:40 Baryon resonance study via photon beam asymmetries in the reaction $\gamma p \to \pi^{0} \eta p$

Multi-meson photoproduction plays a crucial role in the baryon spectroscopy in the high-energy region above 2 GeV. In this region, the intermediate resonances typically have broad widths so that they significantly overlap with each other. The measurement of polarization observables is essential for disentangling these contributions, but experimental data above 2 GeV remain scarce. In particular, there are no existing data on beam asymmetries in the reaction $\gamma p \to \pi^{0} \eta p$ above 2 GeV, and performing such measurements is extremely important.
Photon beam asymmetries represent the extent to which the differential cross section depends on the azimuthal angle of the reaction plane when a linearly polarized photon beam is used. This observable is sensitive to the spin and parity of the intermediate resonances. In reactions with three particles in the final states, such as $\gamma p \to \pi^{0} \eta p$, both quasi-two-body beam asymmetry and three-body beam asymmetry can be measured. These observables provide valuable insight into the contributions of intermediate resonances, the spin alignment of resonances, and the interference among different reaction mechanisms.
The LEPS2/BGOegg experiment utilizes linearly polarized photon beams with energies up to 2.4 GeV and has a large solid-angle electromagnetic calorimeter with world-leading energy resolution, making it ideal for studying reactions with neutral mesons in the final states in the high-energy region.
We measured the quasi-two-body and three-body beam asymmetries in the reaction $\gamma p \to \pi^{0} \eta p$ above 2 GeV for the first time. In this presentation, we report our preliminary results and compare them with the existing Partial Wave Analysis calculations.

Speaker: Toshikazu HASHIMOTO (Research Center for Nuclear Physics, Osaka University)

11:55 On the Trail of Light Exotics: An Experimental Overview

The regime of light mesons still holds many open questions.
Beyond the conventional meson nonets, numerous candidates have been observed that may possess exotic structures, such as glueballs, hybrids, or tetraquarks.
In particular, searching and identifying such exotic states is a challenge among the many broad and overlapping resonances in the highly populated light hadron spectrum. Combining information of different decay- and production mechanisms in coupled channel partial wave analyses using data even from different experiments, helps to disentangle and identify such states.
This does not only minimize effects of ambiguous solutions and systematic effects but more importantly allows for a proper treatment of fundamental constraints as unitarity and analyticity. 
The talk will give a global overview of recent experimental results from various different experiments on the search for exotic hadrons. Special emphasis will be put on the amplitude analysis techniques employed and new technical advancements in the field of hadron spectroscopy.

Speaker: Dr Meike Küßner (Ruhr-Universität Bochum)

12:10 Studies of exotic baryon structure in the light quark sector with the BGOOD photoproduction experiment

The discoveries of the pentaquark states and $XYZ$ mesons in the charmed quark sector initiated a new epoch in hadron physics, where the existence of exotic multi-quark states beyond the conventional valence three quark and quark-antiquark systems has been confirmed. Such states could manifest as single colour bound objects, or evolve from meson-baryon and meson-meson interactions, creating molecular like systems and re-scattering effects near production thresholds. Equivalent structures may be evidenced in the light, $uds$ sector, which is the focus of research at the BGOOD photoproduction experiment at the ELSA accelerator in Bonn, Germany. BGOOD is comprised of a central electromagnetic calorimeter and forward spectrometer, enabling access to low momentum exchange kinematics. This is crucial to study spatially extended, molecular-like structure which may manifest in reaction mechanisms.

Our results in the strangeness sector suggest a dominant role of meson-baryon dynamics which has an equivalence to the $P_C$ states in the charmed sector. This includes structure in $K^0\Sigma^0$ and $K^+(\Lambda(1405)\rightarrow \pi^0\Sigma^0)$ photoproduction at the $K^*Y$ threshold and a peak at the $K^+K^-p$ threshold in $K^+\Sigma^-$ photoproduction which is only evident at very low momentum transfer kinematics.

In the non-strange sector, our measurements of the coherent reactions, $\gamma d \rightarrow \pi^0\pi^0 d$, $\gamma d \rightarrow \pi^0\eta d$ and $\gamma d \rightarrow \pi^0\pi^0\pi^0 d$ exhibit forward differential cross sections an order of magnitude higher than phenomenological model calculations. This is consistent with intermediate dibaryon formation, including the proposed $d^*(2380)$ hexaquark, however other mechanisms, such as final state interactions may yet prove to play dominant roles.

Speaker: Dr Thomas Jude (The University of Bonn)

11:10 → 12:35 Parallel Session B: Hadron-hadron Interactions 3

11:10 Cusp spectroscopy: experimental studies of threshold cusps and hadron-hadron scattering length

Near-threshold molecular-like state may appear as threshold cusp especially when the interaction is not strong enough so that a virtual state is formed instead of a bound state.
The shape of a cusp is strongly related to the scattering length of the two involved hadrons, so that threshold cusp can be used as a novel method to extract hadron-hadron scattering length. In this talk, I will discuss principles of "cusp spectroscopy" and introduce experimental plans at J-PARC. I will also show experimental identification of a threshold cusp and some other related results.

Speaker: Kiyoshi Tanida

11:30 Search for new physics with baryons at BESIII

The BESIII experiment is a symmetric e+e- collider operating at the center of mass
energy from 2.0 to 4.95 GeV. With the world’s largest on-threshold production data
set of 10 billion $J/\psi$, we are able to search for new physics from baryons produced
in $J/\psi$ decay. In this talk, we report the search for BSM particles in the invisible decays of $\Sigma^+$ and $\Xi^-$.
The baryon number violation processes will also be searched for in $J/\psi \to pe$, as
well as in $\Lambda - \bar{\Lambda}$ oscillation in $J/\psi$ decays.

Speaker: Amit Pathak

11:45 Eigenstates in coupled-channel scattering amplitude and their effects on spectrum

Discrete eigenstates, including resonances, can be represented by poles of analytically continuous scattering amplitude in the complex energy plane.
In multi-channel scattering
channels with same flavor quantum number,
the Riemann sheet becomes more complex, and various types of poles appear, not limited to resonances.
In this study, we investigate the relationship between poles located on different Riemann sheets in such multi-channel scattering and discuss how these poles affect the observable spectrum. In particular, we clarify the effect of decay channels on the trajectory of poles in s-wave interactions when the bound state evolves into resonance via a virtual state.
We also focus on several theoretical models based on the chiral unitary method describing meson baryon scattering including Xi(1620) and Xi(1690) resonances as specific examples, and discuss how the pole structure affects the spectrum by studying the effect on the πΣ invariant mass distribution in the Ξc→ππΞ decay. We discuss how the pole structure affects the spectra.

Speaker: Mr Takuma Nishibuchi (TokyoMetropolitanUniversity)

12:00 Investigating the Nature of the Exotic State X(3872) within a Coupled-Channel Framework

The exotic hadron X(3872) lies extremely close to the $\bar{D}D^*$ threshold and exhibits unusual decay patterns, making its internal structure a longstanding puzzle. Near-threshold states like this are highly sensitive to hadronic interactions and model assumptions, and their interpretation requires a unified treatment of mass spectrum and decay properties. In this talk, I present a coupled-channel framework where X(3872) emerges as a mixed state of a $\bar{D}D^*$ molecule and a compact $c\bar{c}$ core. The interaction is constrained by fitting the $T_{cc}^+$ line shape. Using effective field theory and the quark-interchange model, we compute various decay modes, including open-, hidden-charm, and radiative decay channels, and successfully reproduce experimental lineshapes.

Speaker: GUANGJUAN WANG (Japan Atomic Energy Agency)

12:15 Production, Decay and CP violation of baryon-antibaryon pairs

The self-polarization of relativistic electrons or positrons moving in a magnetic field at a storage ring occurs through the emission of spin-flip synchrotron radiation, known as the Sokolov-Ternov effect. The
resulting transverse polarizations of the colliding electrons and positrons, away from the depolarizationresonances, allow for precise investigation of the spin entangled hyperon-antihyperon pairs via virtual photon or charmonium decay. The feasibility study reveals a promising increase in the statistical sensitivity of the CP violation signal after considering the transverse polarizations of the lepton beams.

Speaker: Xu Cao (Institute of Modern Physics, Chinese Academy of Sciences)

11:10 → 12:35 Parallel Session C: Hadrons at finite density & temperature 3

11:10 Hadrons at Finite Density and Temperature: Phases, Degrees of Freedom, and Continuities

The study of hadronic matter at finite density and temperature is important for understanding phenomena ranging from heavy-ion collisions to neutron star interiors and the early universe. In this talk, I will present an overview of the current understanding of the phase structure of strongly interacting matter, focusing on the relevant degrees of freedom—hadrons, quarks, and gluons—and their transitions. A key focus will be the concept of continuity, including the smooth crossover at finite temperature and the possible quark–hadron continuity at high density. I will also discuss recent insights into quarkyonic matter and related intermediate phases, where quarks are partially deconfined while gluons remain confined, offering new perspectives on the nonperturbative dynamics of QCD.

Speaker: Yoshimasa Hidaka (YITP, Kyoto University)

11:30 Direct measurement of the in-medium η' mass spectrum via the η'→γγ decay at the LEPS2/BGOegg experiment

The $\eta^{\prime}$ meson has a larger mass than the other pseudoscalar mesons in the same nonet of flavor SU(3), due to the effect of the axial U(1) anomaly. Since this effect is closely related to chiral symmetry breaking, various theoretical models predict that the mass of the $\eta^{\prime}$ will decrease significantly in a nuclear medium as chiral symmetry is partially restored.
One of the direct methods for studying in-medium $\eta^{\prime}$ mass spectra is to reconstruct the meson’s invariant mass from the four-momenta of its decay products. We have investigated the $\eta^{\prime}$ mass spectra in the $\gamma$+C reaction via the $\eta^{\prime}\to\gamma\gamma$ decay mode using an electro-magnetic calorimeter BGOegg, which offers world-class mass resolution. We analyzed the line shape of the $\gamma\gamma$ invariant mass spectra in detail, and searched for possible differences between $\eta^{\prime}$ mass inside the nucleus and in vacuum.
In this presentation, we will outline our analysis and report the results.

Speaker: Yuji Matsumura (Research Center for Accelerator and Radioisotope Science, Tohoku University)

11:45 Baryonic excitaions in heavy-quark QCD

We investigate the thermodynamic properties of baryonic excitations in heavy-quark QCD. Based on a lattice QCD formulation with $N_{\rm f}$-flavor Wilson fermions, we derive an expression for the grand potential in terms of loop operators in the hopping parameter expansion (HPE) and the cumulant expansion. Using this grand potential, we analytically compute the baryon number susceptibilities and show that the ratio of the fourth- to second-order susceptibility drops discontinuously from unity in the confined phase to 1/9 in the deconfined phase at the leading order of the HPE. This behavior shows that the excitations carrying quark charges change from baryons to quarks at the phase transition. We also investigate their excitation energies in both phases by comparing the analytic expression of the grand potential to that of a lattice Boltzmann gas. We decompose the grand potential in the confined phase into contributions from different flavor-multiplet baryons. Their properties are then qualitatively investigated in the strong-coupling limit.

Reference:
K. Tohme, T.M. Doi, M. Kitazawa, K. Redlich and C. Sasaki, arXiv:2508.09927 [hep-lat].

Speaker: Kei Tohme (Kyoto University)

12:00 Heavy flavor suppression in relativistic heavy-ion collisions

We discuss heavy flavor suppression and anisotropic flow at intermediate momentum, where the heavy-quark mass is non-negligible. In relativistic heavy-ion collisions, heavy meson observables are influenced by numerous factors, including heavy-quark interaction with QGP and hadronization. The collisional and radiative energy loss of heavy quarks can be systematically described by a Boltzmann equation that incorporates the heavy-quark diffusion coefficient [1]. By employing a diffusion coefficient constrained by lattice QCD data, we estimate the momentum dependence of heavy meson observables [2]. The influence of radiative effects is analyzed in the transition region, where the dominant energy loss shifts from collisional to radiative.

[1] Phys. Rev. C 109, 024913 (2024)
[2] Phys. Rev. C 111, 044910 (2025)

Speaker: Juhee Hong (Yonsei University)

12:15 Long-Range N−J/ψ Interaction from an Operator Product Expansion Perspective

Lattice QCD indicates an attractive $N-J/\psi$ interaction with a long-range two-pion exchange tail. To examine this, we use QCD sum rules, extracting the leading dimension-6 four-quark operator that couples to $\pi\pi$ and computing its contribution to the $J/\psi$ mass in nuclear matter. The result is a modest downward shift, smaller in magnitude but qualitatively consistent in sign with the attraction obtained in the lattice QCD, allowing us to analyze the effects of partial chiral restoration on $J/\psi$ and other heavy-quarkonia.

Speaker: Seokwoo Yeo (Yonsei University)

11:10 → 12:35 Parallel Session D: Recent developments in QCD 3

11:10 Gravitational form factors from Continuum Schwinger methods

A symmetry-preserving analysis of strong interaction quantum field equations is used to complete a unified treatment of pion, kaon, and nucleon electromagnetic and gravitational form factors. Findings include a demonstration that the pion near-core pressure is roughly twice that in the proton, so both are significantly greater than that of a neutron
star; parton species separations of the nucleon’s three gravitational form factors, in which, inter alia, the glue-to-quark ratio for each form factor is seen to take the same constant value, independent of momentum transfer; and a determination of proton radii orderings, with the mechanical (normal force) radius being less than the mass-energy radius, which is less than the proton charge radius. This body of predictions should prove useful in an era of experiments that will enable them to be tested.

Speaker: Zhao-qian Yao

11:30 Exclusive photoproduction of vector mesons

The vector mesons photoproduction off proton at high energy is widely assumed to proceed via mechanism that are sensitive to glue physics in the target proton. On the basis of the factorisation theorem, this kind of process can be considered as three separate parts: the fluctuation of the virtual photon into a quark-antiquark pair; the interaction of the quark-antiquark pair with the proton; and the formation of the vector meson from the quark-antiquark pair. In our reaction model, the photon-vector mesons transition amplitudes are described by quark propagators and mesons BSA solved with modern gluon model, the complex interaction between quarks and target proton are quantified as Pomeron exchange. Our results imply that the reaction model can unify both light and heavy vector mesons photoproduction from threshold to very high energy.

Speaker: Lin Tang

11:50 Pion, kaon and proton fragmentation functions

By exploiting crossing symmetry, a unified treatment of the pion, kaon, proton distribution functions (DFs) and fragmentation functions (FFs) was accomplished. It gives insights into the link between two important phenomena in QCD: EHM and confinement. After evolving to higher scale, it provides coherent picture of fragmentation across all parton types. The obtained FFs conform with the physical expectations for FF behaviour on the endpoint domains.

Speaker: Hui-Yu Xing (Nanjing University)

12:10 Flavor asymmetry from the nonperturbative nucleon sea

Recent measurements of the proton’s flavor asymmetry by the SeaQuest/E906 experiment challenge earlier results from NuSea/E866 at large momentum fraction $x$ , underscoring the need for a deeper understanding of the nonperturbative structure of the nucleon sea. A widely invoked theoretical framework is the pion cloud model -- yet it is typically treated perturbatively, despite the intrinsically strong pion-nucleon coupling. In this talk, I demonstrate that physics beyond the one-pion exchange approximation is both significant and highly nontrivial when treated nonperturbatively. Using a simplified scalar version of chiral effective field theory (EFT) formulated on the light front, we perform a fully nonperturbative calculation that consistently incorporates dynamics and renormalization. The results indicate that a complete nonperturbative treatment of chiral EFT is essential to achieve robust, quantitatively reliable predictions -- crucial for meaningful comparison with modern experimental data on the proton’s $\bar{d}/\bar{u}$ asymmetry.

Speaker: Yang Li (University of Science and Technology of China)

12:35 → 14:00 Lunch

14:00 → 15:40 Parallel Session A: Spectroscopy of hadrons 4

14:00 Uncovering the Source of Resonant States

We investigate two-particle scattering with a bare basis state using Hamiltonian Effective Field Theory (HEFT). The resonance is identified as a pole of the scattering amplitude in the complex plane. In this talk, we will study the influence of the bare state on the resonance pole and explore the poles originating from the bare state or coupled channels by analyzing the trajectories of pole positions, as well as the compositeness of bound states.

Speaker: Jia-jun Wu

14:20 Heavy-Light Meson Spectra: A Study in the Relativistic Flux Tube model

Motivated by the recent experimental discoveries of heavy hadrons, we explore the mass spectra of heavy–light mesons within the framework of the relativistic flux tube model. To incorporate heavy-quark symmetry, we employ the j–j coupling scheme and analyze the spin-dependent mass splittings, which arise from interactions such as spin–orbit, spin–spin, and tensor terms. Our calculated masses for orbitally and radially excited states show close agreement with the available experimental measurements of heavy–light mesons. While the results reproduce earlier quark model predictions for low-lying states with good reliability, some deviations appear in higher excitations. Based on the consistent description of the well-established states, we propose spectroscopic assignments for the higher-mass resonances reported in recent experiments. This study thus provides useful guidance for upcoming experimental searches of radial and orbital excitations in the heavy–light meson sector.

Speaker: Pooja Jakhad

14:35 Determination of Scattering Length from Lineshape of Cross Sections Depending on Incident Pion Momentum for $\pi^- p → \phi n$ near Threshold

Hadron-hadron interactions result from low-energy QCD dynamics. Although the phi-nucleon interaction is fundamental to be understood in hadron physics, we do not know whether this interaction is weak or strong. Historically, the interaction has been considered to be weak for a long time owing to the Okubo-Zweig-Iizuka (OZI) rule that a reaction including non-connecting quark lines is suppressed. The weakly interacting phi-nucleon system is supported by analysis of the photoproduction reactions with a vector-meson dominance model. Recently, the strongly interacting is suggested from the momentum correlation function in the high energy proton-proton collision and the lattice QCD calculations. Currently, we have controversial low-energy $\phi N$ scattering parameters.
We plan to measure the cross section for $\pi^- p → \phi n$ near threshold. We find that we can extract the scattering length and the effective range of the phi-nucleon interaction by analyzing the total cross section data to be obtained using the scattering equation with final-state interactions. In this presentation, we will present expected uncertainties of the $\phi$-nucleon scattering length for a few-days measurement

Speaker: Akinori Higashi (RCNP Osaka University)

14:50 DeepQuark: deep-neural-network approach to multiquark bound states

For the first time, we implement the deep-neural-network-based variational Monte Carlo approach for the multiquark bound states. We design a novel and high-efficiency architecture, DeepQuark, to address the challenges in multiquark systems. Our method demonstrates competitive performance with state-of-the-art approaches in the nucleon, doubly heavy tetraquark, and fully heavy tetraquark systems. Notably, it outperforms existing calculations for pentaquark systems. DeepQuark holds great promise for extension to larger multiquark systems, overcoming the computational barriers in conventional methods. It also serves as a powerful framework for exploring confining mechanism beyond two-body interactions in multiquark states, which may offer valuable insights into nonperturbative QCD and general many-body physics.

Speaker: Wei-lin Wu (Peking University)

15:05 Observations of Charmonium and Charmonium-like States Decaying into Final States with Baryons

Investigating decays of charmonium and charmonium-like states into final states
involving baryons provides crucial insights into the coupling mechanisms between
heavy quarkonia and baryons. These studies also provide methods for exploring
undetected excited nucleons and hyperons, offering a unique window into the baryon
spectrum. In this talk, I will present recent progress from the BESIII experiment,
highlighting novel observations of charmonium and charmonium-like states decaying
into baryon-involving final states. These findings advance our understanding of QCD
dynamics in the charmonium mass region and underscore the potential of baryonic
transitions in probing exotic hadronic configurations.

Speaker: Weimin Song (Jilin University College of Physics (CN))

15:20 Light Baryon Spectroscopy at BESIII

Based on the large samples of 10 billion J/ψ and 2.7 billion ψ(3686) events accumulated at the BESIII detector, the recent progresses on baryon spectroscopy, including the amplitude analyses of ψ(3686) $\to p \bar{p} \pi^0$, ψ(3686) $\to p \bar{p} \eta$, and ψ(3686)$\to \Lambda \bar{\Sigma} \pi$, will be presented. The perspectives on the baryon spectroscopy at BESIII will also be discussed.

Speaker: Ronggang Ping

14:00 → 15:40 Parallel Session B: Hadron-hadron Interactions 4

14:00 Exotic hadrons as heavy hadronic molecules and their partner structures

In recent years, there has been growing interest in exotic hadrons that exhibit structures beyond the conventional hadron picture, where baryons are treated as three-quark states ($qqq$) and mesons as quark--antiquark pairs ($q\bar{q}$). In particular, in the charm sector, many exotic hadrons referred to as $XYZ$, $P_c$, and $T_{cc}$ states have been reported in accelerator experiments since the discovery of the $X(3872)$ by the Belle experiment in 2003. Most of these states appear near hadron thresholds and thus are considered as (quasi-)bound hadronic molecular states composed of multiple hadrons, The hadronic molecules are similar to atomic nuclei that are nuclear self-bound systems with a small binding energy. However, the hadron--hadron interactions that is responsible for binding such states are not yet fully understood. Understanding hadronic interactions is essential for uncovering the dynamics of low-energy QCD.

Heavy hadrons containing charm quarks are unstable, making it difficult to study their interactions via scattering experiments, unlike in traditional nuclear force studies. Recently, however, approaches using lattice QCD simulations on supercomputers and femtoscopy in high-energy nuclear collisions have begun to provide (numerical) experimental data on heavy hadron interactions. These approaches will provide an opportunities to study the heavy hadron interactions.

In this talk, we discuss hadronic molecules including heavy mesons (such as $D$ or $B$ mesons), focusing on their bound and resonant states using theoretical analysis. Heavy mesons are expected to be constituents of many hadronic molecular states, and thus understanding their interactions is very important to investigate the exotic hadrons. In the heavy hadron sector, the heavy quark symmetry is important, which induces channel coupling effects and also predicts spin partner states. We study bound state properties of hadronic molecules and also discuss partner states of these exotics, predicted by symmetries.

Speaker: Yasuhiro Yamaguchi (Nagoya University)

14:20 Femtoscopic study on D^0 D^0* bar interaction

We study the D^0 D^0* bar momentum correlation to investigate the structure of X(3872) and Z_c(3900) using the simple hadronic model with
the separable interactions. The model parameters are fixed so as to reproduce the observed masses of X(3872) and Z_c(3900).

Speaker: Makoto Takizawa

14:35 Di-Jpsi scattering with the quark Pauli-blocking effects

The scattering states of the double-charmonium, such as $J/\psi J/\psi$, $\eta_c J/\psi$, and $\eta_c\eta_c$, are investigated by a simplified quark cluster model focusing on the Pauli principle over the quarks. We found that its effects on the $c\bar c c\bar c$ quark system can be expressed by a two-meson potential that has a node. With such a potential, the scattering phase shifts have a node at a specific energy. The effects can be seen in the cross sections, and the $J/\psi J/\psi$, $J/\psi\eta_c$, and $\eta_c\eta_c$ spectra as well as in the phase shifts. We will also demonstrate how the correlation function from heavy ion collisions is affected by these effects.

Speaker: Sachiko Takeuchi

14:50 Doubly heavy tetraquark and $\bar{D}^{(\ast)}\Xi^{(\ast)}_{cc}$ and $\Xi^{(\ast)}_{cc}\Xi^{(\ast)}_{cc}$ as partners of doubly charmed tetraquark

One of the most intriguing exotic hadrons is the doubly charmed tetraquark $T_{cc}$, which was reported by the LHCb experiment in 2022.
Due to its extremely small binding energy, $T_{cc}$ is considered to be a hadronic molecule rather than a tightly bound compact state.
Motivated by this interpretation, we have investigated $T_{cc}$ as a hadronic molecular state based on the one-boson exchange model, while respecting heavy quark symmetry (HQS).

Furthermore, we extended our study to the doubly bottom tetraquark $T_{bb}$, which can be regarded as a heavy quark flavor partner of $T_{cc}$.
In addition, we explored the systems $\bar{D}^{(*)} \Xi_{cc}^{(*)}$ and $\Xi_{cc}^{(*)} \Xi_{cc}^{(*)}$, which may be viewed as superflavor partners of $T_{cc}$.
Our analysis reveals the existence of a variety of bound and resonant states in the $T_{bb}$, $\bar{D}^{(*)} \Xi_{cc}^{(*)}$, and $\Xi_{cc}^{(*)} \Xi_{cc}^{(*)}$ sectors.

Moreover, we have investigated the heavy quark spin (HQS) multiplet structures by employing the light cloud spin basis, which enables a clear classification of the states according to their HQS multiplet properties.

Speaker: Manato Sakai (Nagoya University)

15:05 Internal structure of exotic hadrons with coupled channel potential in relation with scattering observables

We study the properties of the hadron-hadron potentials and quark-antiquark potentials from the viewpoint of the channel coupling[1]. We introduce the effective hadron-hadron potential with coupled to the quark channel.
As an application, we construct a coupled-channel model of $c\bar{c}$ and $D\bar{D}$ to describe exotic hadron $X(3872)$[2].

To investigate the internal structure of the $X(3872)$, we introduce the direct 4-point interaction of the hadron channel, in addition to the contribution of the coupling to the quark channel. We study the dominant compornent of the $X(3872)$ by annalyzing wavefunctions, compositteness, scattering length, effective range, and phase shift. We study the changes of these quantities
by varying model parameters such as quark channel enrgy, cut-off, and potential strength of hadron channel in addition to a physical obsearvable binding energy.

[1] I. Terashima and T. Hyodo, Phys. Rev. C 108, 035204 (2023).
[2] M. Takizawa and S. Takeuchi, PTEP 2013, 093D01 (2013).

Speaker: Ibuki Terashima (Tokyo Metropolitan University)

14:00 → 15:40 Parallel Session C: Hadrons from heavy-ion collisions 2

14:00 Bayesian Inference for Heavy-Ion Collisions: Opportunities and Challenges

Over the past decade, Bayesian inference has become an invaluable tool in heavy-ion collision modeling. By integrating input from both experimental and theoretical perspectives, it bridges two traditionally separate domains. Progress in this framework relies on both high-precision experimental measurements and theoretical developments that yield more accurate predictions. This dual requirement positions Bayesian analyses as a collaborative frontier, offering opportunities for both experimentalists and theorists.
The recent availability of high-precision measurements paves the way for broader and more thorough studies. Historically, Bayesian inference has primarily been used to investigate the transport properties of the quark-gluon plasma (QGP) produced in heavy-ion collisions, successfully constraining the temperature dependence of specific shear and bulk viscosities. More recent studies have extended the method to explore initial-stage dynamics, nuclear structure, and jet quenching.
In this talk, I will discuss the current and future roles of Bayesian inference, highlighting its advantages and limitations. Finally, I will outline how we can further develop and refine the framework to achieve a more consistent and comprehensive understanding of QGP matter.

Speaker: Dong Jo Kim (University of Jyvaskyla (FI))

14:20 Production of charm-strange mesons at \sqrt{s_{NN}}=5.02 TeV in heavy ion collisions

We discuss charm-strange mesons in heavy-ion collisions at \sqrt{s_{NN}} = 5.02 TeV, focusing on their production based on the coalescence model. Starting from the investigation on the transverse momentum distribution of both charm and strange quarks, we evaluate the yield and transverse momentum distribution of Ds, Ds, Ds0(2317), and Ds1(2460) mesons. We also present the transverse momentum distribution of phi and D0 mesons and discuss, in particular, the transverse momentum distributions in both two and four-quark states for Ds0*(2317) mesons. We show that our results agree well with experimental measurements for the Ds meson and argue that the strangeness enhancement has a significant influence on the production of charm-strange mesons in heavy-ion collisions.

Speaker: Sungtae Cho

14:40 Spin polarization from hadrons to (anti-)(hyper-)nuclei in heavy-ion collisions

Particles of non-zero spin produced in non-central heavy-ion collisions are expected to be polarized along the direction perpendicular to the reaction plane because of their spin-orbit interactions in the produced matter. In this talk, I will show that the hypertriton, which is the lightest hypernucleus, is also polarized in these collisions. I will demonstrate that the polarization and decay pattern of hypertriton provides a unique tool to decipher the spin structure of hypertriton wavefunction. I will further discuss the possibility of studying the spin correlations among nucleons and Λ hyperons in the produced hadronic matter from the measured Λ polarization in non-central heavy-ion collisions.

Reference: Kai-Jia Sun et al., Phys. Rev. Lett.134.022301 (2025)

Speaker: Dr KaiJia Sun (Institute of Modern Physics, Fudan University, Shanghai, China)

14:55 Multiplicity distributions in DIS for heavy nucleus

In this talk, we will discuss the multiplicity distribution in deep inelastic processes on a heavy nucleus in the framework of high-energy QCD. We will present a new derivation for the cross sections of productions of $n$ gluons in the final states ($\sigma_n$), obtained using the dipole picture of high-energy QCD and consistent with the equations derived from the Abramovsky-Gribov-Kancheli (AGK) cutting rules. These equations describe the production of $n$ gluons measured by the detector. We solve them in coordinate space by using the homotopy method, which provides an analytical solution for the first iteration and a systematic procedure for the higher-order corrections. For specific initial conditions, we also found a simplified analytical solution for $\sigma_n$ in momentum space and calculated the entropy for the produced gluons: $\ln N_{DIS}$, where $N_{DIS}$ is the multiplicity in the deep inelastic scattering process, confirming previous ideas on this subject.

Speaker: José Garrido

15:10 Measurement of $\chi_{c}$ production in pPb collisions with CMS

The nuclear modification of quarkonium production serves as crucial evidence for the deconfined QCD medium production in nuclear collisions. This modification is influenced not only by medium dissociation but also by a collection of initial and final state effects. The production of excited charmonium states in pPb collisions presents a controlled setting to further investigate these phenomena. Notably, the production of the $\chi_c$ mesons offers valuable insights into the feed-down processes and binding energy dependencies of charmonia in nuclear collisions, as their mass is situated between the ground state and the $\psi(2S)$.

In this presentation, we report on our CMS measurements of $\chi_c$ meson production in pPb collisions. We report on the relative production rates of $\chi_{c1,2}$ in relation to $J/\psi$. Our analysis measures the cross-section ratios as a function of particle transverse momentum, rapidity, and event activity. These results are then compared with other LHC measurements and theoretical predictions, providing deeper insight into the production mechanisms of $\chi_c$ states in nuclear collisions.

Speaker: Jeongho Kim (Sejong University (KR))

15:25 Nuclear modification of heavy flavor hadron decayed dielectrons in relativistic heavy-ion collisions

Dielectrons from open charm hadron decays provide a promising probe of heavy-quark interaction with the quark-gluon plasma (QGP) in relativistic heavy-ion collisions, and meanwhile constitute a crucial background of the invariant mass spectra of dielectrons from which the temperature of the QGP is extracted. So far, effects of medium modification of heavy quarks on dielectron spectra have been rarely investigated. In this work, we use a linear Boltzmann transport model to describe heavy quark scatterings with the QGP, which incorporates both Yukawa and string interactions. By converting heavy quarks into heavy flavor hadrons via a hybrid fragmentation-coalescence model and further decaying them into electrons via PYTHIA, we study the angular correlations of dielectrons and their invariant mass spectra in heavy-ion collisions at RHIC and LHC energies. Our results show that the angular correlations of $e^+e^-$ pairs are sensitive to the interaction mechanisms between heavy quarks and the QGP. In particular, the energy loss is effective in suppressing the away-side peak of their angular distributions, while the collective flow of the QGP enhances the near-side peak. Additionally, we find that both energy loss of heavy quarks and their hadronization mechanism affect the invariant mass spectra of dileptons, which can further lead to a sizable systematic uncertainty of the value of the QGP temperature extracted from the dilepton spectra.

Speaker: Ms Lejing Zhang (Shandong University)

14:00 → 15:40 Parallel Session D: Structure of hadrons 2

14:00 Baryon structure from hard exclusive reactions

In this talk, I will review recent advances in the study of baryon structure using high-energy probes through hard exclusive reactions. Particular emphasis will be placed on the role of generalized parton distributions (GPDs) as a framework for accessing multidimensional information on the internal structure of baryons. I will discuss how three-dimensional imaging and momentum-space tomography of the nucleon and its excited states provide novel insights into the spatial and dynamical distributions of quarks and gluons. Special attention will be given to nucleon-to-resonance transition GPDs and their connection to fundamental QCD observables, such as the form factors of the energy–momentum tensor. The presentation will survey the status of
theoretical developments, phenomenological studies, and dedicated experimental programs aimed at the partonic structure of baryons.

Speaker: Kirill Semenov-Tian-Shansky (PNPI)

14:20 The parity-odd structure function of the nucleon from the Compton amplitude in lattice QCD

The dominant contribution to the theoretical uncertainty in the extracted weak parameters of the Standard Model comes from the hadronic uncertainties in the electroweak box diagrams, i.e. $\gamma-W^\pm/Z$ exchange diagrams. A dispersive analysis relates the box diagrams to the parity-odd structure function, $F_3$, for which the experimental data either do not exist or belong to a separate isospin channel. Therefore a first-principles calculation of $F_3$ is highly desirable.

In this contribution, I report on the QCDSF Collaboration's calculation of the moments of the $F_3^{\gamma Z}$ structure function from the forward Compton amplitude at the SU(3) symmetric point. We focus on the first moment of $F_3^{\gamma Z}$ for a range of $Q^2$ values. We discuss the implications of our results for the electroweak box diagrams along with the possibility of a determination of the strong coupling constant via the Gross-Llewellyn Smith sum rule.

Speaker: Dr K. Utku Can (The University of Adelaide)

14:35 Exploring transition generalized parton distributions in non-diagonal hard exclusive reactions at EIC

Generalized parton distributions (GPDs) for hadron-to-resonance transition establish a framework for understanding the internal structure of hadronic excitation in QCD. Non-diagonal hard exclusive reactions, such as deeply virtual Compton scattering (DVCS) and meson production (DVMP) involving $N \to N^*$ transition, serve as useful channels for empirical access to the corresponding transition GPDs in the generalized Bjorken kinematics. The planned Electron-Ion Collider (EIC) is expected to broaden the accessible kinematic range and enable the measurement of various spin asymmetries. In this context, we examine the feasibility of non-diagonal DVCS and DVMP processes, such as $e^- N \to e^- \gamma \Delta$ and $e^- N \to e^- \pi \Delta$, by presenting differential cross sections and various asymmetries under EIC kinematics. We also estimate the cross section of strange meson DVMP with $N\to Y$ transition, which is sensitive to flavor non-diagonal GPDs. These results may provide a useful benchmark for examining suitable kinematic conditions to study transition GPDs in the future EIC program. In addition, we briefly discuss the application of covariant light-front dynamics to mesonic transition GPDs, in particular $\pi\to\rho$, while a generalized description of pion-to-resonance transition is formulated within the framework of the $\pi\to\pi\pi$ GPDs.

Speaker: Sangyeong Son (Kyungpook National University)

14:50 The EMFFs of the hyperons

MFFs of nucleons have been widely studied by both experiment and theory. However, the research on hyperons are not so dedicated. In our present work, we analyzed EMFF of the hyperon. The potentials are calculated from SU(3) chiral effective field theory and the scattering amplitudes are solved by Lippmann-Schwinger equation, the amplitudes of electron-positron annihilating into hyperon-anti-hyperon are obtained by the distorted wave born approximation. The latest data are fitted to fix the unknown couplings. Then, the EMFFs are extracted and analyzed. We also discuss the possible oscillation of the EMFFs of the hyperon. Further measurements from the experiment would be quite helpful to study the EMFFs of the hyperons.

Speaker: jiali shi

15:05 Electromagnetic form factors of the nucleon in an effective chiral theory

We investigate electromagnetic properties of nucleons within the framework of an effective chiral theory derived from the QCD instanton vacuum. It was based on the nonlocal $2N_f$ quark interactions, which can be bosonized to be the nonlocal effective chiral action with the momentum-dependent dynamical quark mass. A great merit of this approach is that it does not have any adjustable free parameter, and provides a natural regulator to tame the divergent quark loops. On the other hand, the momentum-dependent quark mass causes the breaking of the gauge invariance. Having restored it, we obtain a so-called nonlocal contribution to the ordinary electromagnetic current. Using this current, we compute the electromagnetic form factors of the proton and neutron, as well as their charge and magnetization distributions. The results are in good agreement with the experimental data, and reveal unique features of the nonlocal interactions in both the electric and magnetic properties of the nucleon.

Speaker: Hui-Jae Lee (Inha University)

15:20 Chiral-odd generalized parton distributions of spin-1/2 baryons

We present the tomographical structure of spin-1/2 baryons by studying the nonforward matrix elements of lightlike correlation functions of the tensor current. At the leading twist, with the tensor current, four chiral-odd distributions are in count. We calculate these distributions in a diquark spectator model with light-front formalism by considering purely transverse momentum transfer, i.e., zero skewness. Predictions for the nucleons and light hyperons are studied, emphasizing the difference arising from their different quark flavors.

Speaker: Harleen Dahiya

15:40 → 16:10 Coffee break

16:10 → 18:00 Parallel Session A: Spectroscopy of hadrons 5

16:10 Exploring the intersection of deep learning and hadron spectroscopy

The difficulty of identifying which observed near-threshold signals are part of the hadron spectrum triggered the introduction of alternative analysis tools. The deep learning framework, combined with S-matrix program offers a unique way of studying near-threshold signals. Even if the exact form of the S-matrix is not accessible, generic line shapes can be generated by relying solely on the generic properties expected from a scattering amplitude such as unitarity and analyticity. The subtle features of the generated line shapes can be used to teach a deep neural network to identify the analytic structure of the relevant amplitude in a given experimental data. In this talk, we review some of the recent development in the use of deep learning in hadron spectroscopy to analyze seemingly ambiguous interpretations of near-threshold signals. We cite some examples of how deep learning can be used to identify the likely pole structure associated with a given reaction and how to distinguish them from purely kinematical enhancements.

Speaker: Dr Denny Lane Sombillo (University of the Philippines Diliman)

16:30 Valence quark structure of the $\rho$-meson using the light-cone quark model

Understanding the valence quark structure of spin-$1$ mesons is challenging due to their rich spin polarization states. In this context, generalized parton distribution functions (GPDs) play an important role in describing the spatial structure. In this work, we investigate the unpolarized GPDs of the $\rho$-meson using the light-cone quark model in an asymmetric momentum frame. Using these, we calculate various physical properties such as the charge form factor, magnetic form factor, and quadrupole form factor. We also predict the structure functions relevant to the Rosenbluth scattering cross section for the $\rho$-meson. Finally, we derive the parton distribution functions corresponding to the unpolarized GPDs at the model scale and at higher energy scales via the DGLAP evolution.

Speaker: Harleen Dahiya

16:45 Determination of the polarization observables T,P and H in the reaction $\gamma$p $\rightarrow$ p$\pi^0$

The CBELSA/TAPS experiment conducts baryon spectroscopy experiments to
better the understanding of the exitation spectra of nucleons.
The short lifetime of the exited states lead to strongly overlapping resonances, making it
experimentally and theoretically challanging to determine the exact number of exited
nucleon states and their properties.
Using a polarized beam, a polarized target or by measuring the polarization
of the recoil nucleon allows access to single or double polarization
observables, that are needed for an unambiguous solution of the partial
wave analysis.
The CBELSA/TAPS experiment in Bonn provides a polarized pho-
ton beam as well as a longitudinally or transversely polarized target,
allowing for the determination of single and double polarization ob-
servables. The Crystal Barrel (CB) calorimeter, together with the
MiniTAPS calorimeter in forward direction, cover close to $4\pi$ of the solid
angle, which is crucial for the precise determination of polarization observables.
This talk will present results of the polarization observables T, P and H, in
the photon energy range between 600MeV and 3200MeV, providing insight into further energy regions for P and H than was available before. The data was collected after the recent upgrade of the CB calorimeters readout electronics and these results are compared to
previous data and model predictions.

Speaker: Sebastian Ciupka (University of Bonn)

17:00 Partial Wave Analysis for Pion & Proton Induced Resonance Studies in the HADES Experiment

The High Acceptance Di-lepton Spectrometer (HADES) collaboration at GSI plays a crucial role in exploring baryonic resonance characteristics and their decay channels. The unique pion-beam facility at GSI enables the direct formation of baryonic resonances at a fixed center of mass energy ($\sqrt{s}$) in the S-channel. This provides a distinct advantage over proton-induced reactions and complements photo-induced studies conducted at other facilities. Partial Wave Analysis (PWA) techniques are indispensable for unraveling the intricate coupling of these resonances to various final states, particularly those involving two and three pseudoscalar meson production. HADES has a particular interest in understanding the role and medium modification of vector mesons in baryon-dense matter, especially in the context of heavy-ion collisions. Elementary pion-induced reactions on the proton, coupled with rigorous PWA, will yield unprecedented insights into the couplings of baryonic resonances to $\rho N$ and $\omega N$ final states. Such studies are vital for shedding light on phenomena like the melting of the $\rho$ meson in heavy-ion collisions and the role of intermediary vector mesons in dilepton emissions.

In anticipation of a more comprehensive exploration of the resonance regions in pion-nucleon and nucleon-nucleon collisions a modular Partial Wave Analysis software package is currently under development. This experiment-agnostic package implements advanced frameworks, including the K-Matrix and N/D methods, designed for a refined and robust mapping of these resonance regions. Crucially, the software also incorporates a dedicated baryon pseudoscalar fit based on the established JuBo model, which leverages a coupled-channel approach for nucleon interaction with pseudoscalar mesons. This implementation in the software primarily allows for the comparison of the model's predictions (derived from electro- and photoproduction data) to proton-proton data, enabling the estimation of contributions from different resonances and coupled channels. This development is particularly timely given the approval of significant pion beam time at the GSI facility for the next two years, specifically targeting the third resonance region. Furthermore, a proposed pion beam experiment at the J-PARC facility in Japan is anticipated to complement the pion beam experiments at HADES, underscoring the long-term importance and applicability of this versatile PWA framework. We will present the current status of this software, showcasing illustrative fits from both pion-proton reactions in the second and third resonance regions, and proton-proton reactions at 4.5 GeV beam kinetic energy, demonstrating its capabilities and the significant potential of this new analytical framework for the upcoming experimental campaigns.

Speaker: Ahmed Foda

17:15 $K$-matrix Approach to the Three-Pole Structure of the $P_{c\bar{c}}(4312)^{+}$ Pentaquark Candidate

Interpreting peaks in the scattering data becomes further complicated when the observed structure appears near an established threshold channel due to possible effects of near-threshold phenomena. An example is the hidden-charm pentaquark state $P_{c\bar{c}}(4312)^{+}$ in the $\Lambda_{b}^{0} \xrightarrow{}J/\psi K^{-}p$ decay which appears near the $\Sigma_{c}^{+}\bar{D}^{0}$ threshold. We address this issue by fitting the experimental data using a two-channel $K$-matrix parametrization which accounts for the effect of the nearby threshold while ensuring the unitarity of the $S$-matrix. The model also includes the inelastic scattering element $T_{12}$ to accurately capture the lineshape beyond the $\Sigma_{c}^{+}\bar{D}^{0}$ threshold. The resulting fit reveals a three-pole structure with one pole appearing on each unphysical Riemann sheet. The three-pole configuration agrees with an analysis that implemented a model-independent framework. The obtained pole parameters from our model support a hybrid interpretation of the pentaquark as a compact state, possibly contaminated by a virtual pole in the fourth Riemann sheet.

Speaker: Klarence Tomas Cervantes (University of the Philippines Diliman)

17:30 Measurement of the $\Omega(2012)$ baryon at the LHC

The ALICE Collaboration has observed the $\Omega(2012)$ baryon via its decays to $\Xi^{-}K^{0}_{S}$ in high-multiplicity proton-proton collision at $\sqrt{s}=13$ TeV at the LHC. This observation, which has a significance of 15 $\sigma$, corroborates the discovery of this particle by Belle in 2018. The measured mass and width values are consistent with those reported by Belle, confirming that the Omega(2012) has a rather narrow width for a particle that decays strongly. The first measurement of a $p_{\rm T}$ spectrum and yield for the $\Omega(2012)$ is also reported. In combination with thermal model calculations, these results can be used to obtain absolute branching ratios for two-body decays of the $\Omega(2012)$. The width and branching-ratio measurements provide further support for the hypothesis that the $\Omega(2012)$ baryon has spin 3/2. This presentation will describe the analysis technique and discuss the results in comparison to previous measurements and theoretical models.

Speaker: Prof. Anders Garritt Knospe (Lehigh University)

17:45 Internal structure of the Pion and kaon

Understanding the internal structure of hadrons remains one of the key challenges in the non-perturbative regime of QCD. To gain a comprehensive insight into the internal dynamics of the pion and kaon, we have computed the valence quark distributions using parton distribution functions (PDFs), transverse momentum-dependent distributions (TMDs), and generalized parton distributions (GPDs). Our results have been systematically compared with available phenomenological extractions, lattice QCD simulations, and experimental data. Furthermore, by analyzing the GPDs, we have extracted the spatial distributions of pressure and shearing forces inside the pion, providing valuable information about its mechanical structure.

Speaker: Satyajit Puhan (National Institute of Technology Jalandhar)

16:10 → 18:00 Parallel Session B: Hadron-hadron Interactions 5

16:10 Pole-Expansion of Two-Hadron Imaginary-Time Correlation Function -a new method of analysis for unstable states in lattice QCD-

We report on our analysis of the pole expansion of the two-hadron imaginary-time correlation function.
We first explain the general idea that the imaginary-time correlation function is expressed as a sum of the pole terms, the Mittag-Leffler expansion, in terms of the uniformization variable, which makes the S-matrix single-valued.
We then derive explicit expressions of the pole expansion for the single-channel (ρ meson) and two-channel (Λ(1405)) examples and demonstrate that the pole expansion actually holds employing phenomenological models, the vector-dominance model for the ρ meson and the chiral unitary model for Λ(1405).
From this observation we propose the pole expansion as a method to extract information of unstable states such as masses and widths from the two-hadron imaginary-time correlation functions obtained by lattice QCD simulations.
We also discuss how we define unstable states in finite box and their finite-size effects.

Speaker: Osamu Morimatsu (KEK)

16:30 Estimation of potential size based on momentum distribution of constituent particle

The spatial size is one of the fundamental quantities that characterize the properties of hadrons. Especially for exotic hadrons, the size has important implications for understanding their internal structure. $\Lambda(1405)$ is considered to be a $\overline{K}N$ bound state with 30 MeV of binding energy. 30 MeV is larger than that of ordinary nuclei, but it is unlikely to significantly change the structure of $\overline{K}$ and $N$. Similarly, nuclei containing a $\overline{K}$ may have a larger binding energy and exhibit unique properties compared to ordinary nuclei. We are interested in the size of $\overline{K}$ nuclei and aim to clarify it experimentally. There is a plan of creation experiment of a $\overline{K}NNN$ nucleus at J-PARC. To estimate the size, we focus on one of the decay processes of $\overline{K}NNN$, namely the three-body decay into $\Lambda NN$. In this process, $\overline{K}$ meson is absorbed by two nucleons and decays into $\Lambda$ and $N$. The remaining $N$ acts as a spectator and preserves information about the original nucleus [1].
Our aim is to investigate the relationship between the momentum distribution of internal particles and the overall system size. Here, we regard the radius of the potential obtained from the independent particle picture as the system size. We calculate the spatial and momentum distributions of the wave function for potentials with various parameters and compare them with the potential radius. For larger binding energy, the wave function is distributed inside the poteitnal region. In such a situation, the sizes of mean radius and potential radius are comparable, and the product of the standard deviation of radius and momentum of the wave function gets close to the smallest value. Thus, we can estimate the sizes of mean radius and potential radius from the mean momentum. For smaller binding energy, the wave function spreads out from the potential region due to the tunneling effect. Even in such a situation, we find that the momentum distribution remains strongly correlated with the potential radius [2].

[1] P. Kienle, Y. Akaishi, and T. Yamazaki. Phys. Lett., B632:187–191,
2006.

[2] E. Kawamura, K. Murakami, D. Jido, in preparation

Speaker: Mr EISUKE KAWAMURA (Institute of Science Tokyo)

16:45 The source of flavor SU(3) breaking on axial vector mesons as chiral partners of vector mesons

The chiral partner plays an important role in the chiral symmetry breaking. To investigate chiral partners in the finite density is equivalent to study how the chiral symmetry is broken.
However, when we consider the axial vector mesons, whose chiral partners are vector mesons, their detailed structure remains unclear. To investigate the axial vector meson structure, we focus on the SU(3) breaking effect on the axial vector mesons, and find that their SU(3) breaking effect could be different from vector mesons. The difference is that the axial vector octet masses could be accidentally degenerate and axial vector singlet could be split.
In this study, we consider the SU(3) breaking effect using the linear sigma model, which reflects the property of chiral partners. We find that the axial vector meson octet could be degenerate and singlet split. This result will give a new insight for the understandings of axial vector mesons and their chiral partners.

Speaker: Yoshito Nakane (Institute of Science Tokyo)

17:00 Probing Baryon Number Transport and Strangeness Production Dynamics with Hyperon-kaon Correlations

The observation of a positive net hyperon yield in the mid-rapidity region of nuclear collisions at RHIC energies suggests that baryon number can be transported from the initial-state nucleons to hyperons across the rapidity gap—from beam rapidity to mid-rapidity. The dynamics for such baryon number transport are an interesting subject of theoretical and experimental investigations. Recently the gluon junction model, positing that the Y-shaped gluonic junction in proton and neutron may carry the baryon number, has attracted many interest, and the gluon junction interactions may be an effective mechanism of baryon number transport over a large rapidity gap. Given the conservation of strangeness in hyperon production, we utilize hyperon–kaon correlations as a sensitive probe for investigating baryon number transport dynamics. In this study, we present an analysis of hyperon–kaon correlations in p+Au collisions at $\sqrt{S_{NN}} = 39$ and $62$ GeV, simulated using both AMPT and UrQMD models. Furthermore, we discuss implications of both the strangeness conservation and the baryon number transport dynamics on model predictions, and propose to use these results as a baseline reference for future experimental measurements.

Speaker: Siyuan Ping (复旦大学)

17:15 Hyperon-nuclon intetraction through the K^-d→πΛN reaction.

In this talk we report analytic calculations of the $\Lambda N$ invariant-mass spectrum for the $K^-d\rightarrow\pi\Lambda N$ reaction. Focusing on the spin S = 1, isospin I = 1/2 $\Sigma N$–$\Lambda N$ coupling, we evaluate its sensitivity to the scattering length near the $\Sigma N$ threshold. In addition to comparisons with previous experimental data, we discuss the dependence on the deuteron wave function and on the meson–baryon amplitudes.

Speaker: Shunsuke Yasunaga

17:30 Compositeness of near-threshold states in charged hadronic systems

Understanding the internal structure of exotic hadrons is one of the major goals in hadron physics. In recent years, a increasing number of exotic hadrons have been observed, many of which appear near two-hadron scattering thresholds. Possible internal structure of such states includes the hadronic molecule and compact multiquark components. To investigate their structure, we study near-threshold states using the compositeness [1], which quantifies the hadronic molecular component in the wavefunction. In our previous work, we clarified the internal structure of near-threshold states in short-range $s$-wave two-body scattering systems based on the low-energy universality. We found that the shallow bound states tend to exhibit hadronic molecular dominant structures [2], while resonances above the threshold do not [3]. However, there also exist near-threshold states in systems where both short-range and Coulomb interactions are present, such as scatterings between charged hadrons. Although the Coulomb interaction is generally weaker than the short-range force, it cannot be neglected in the low-energy region near the threshold. For example, whether systems like ${}^8$Be nucleus or $\Xi^- \alpha$ are bound or not is known to depend sensitively on the presence of the Coulomb interaction [4,5].

In this work, we focus on near-threshold states in systems governed by both short-range and Coulomb interactions. We employ a low-energy scattering framework characterized by the Coulomb-modified scattering length $a_s$ and effective range $r_e$ [4,6]. We calculate the compositeness to quantify the internal structure and show that the near-threshold behavior is determined by the competition between the short-range and Coulomb interactions. When the Bohr radius $a_B$ is larger than the magnitude of the effective range $|r_e|$, the universal behavior driven by the short-range interaction emerges before the Coulomb interaction becomes dominant. In this case, the compositeness increases near the threshold as a remnant of the short-range universality. On the other hand, if $a_B < |r_e|$, the compositeness does not increase even near the threshold, because the system no longer exhibits universal behavior due to the dominance of the Coulomb interaction [7]. As an application of this framework, we discuss the internal structure of exotic hadrons.

[1] T. Kinugawa, T. Hyodo, Eur. Phys. J. A 61, no.7, 154 (2025).
[2] T. Kinugawa and T. Hyodo, Phys. Rev. C 109, 045205 (2024).
[3] T. Kinugawa and T. Hyodo, arXiv:2403.12635 [hep-ph].
[4] R. Higa, H. W. Hammer, and U. van Kolck, Nuclear Physics A 809, 171 (2008).
[5] Y. Kamiya, A. Jinno, T. Hyodo, and A. Ohnishi, arXiv:2409.13207 [nucl-th].
[6] W. Domcke, Atom. Mol. Phys. 16 359 (1983).
[7] T. Kinugawa and T. Hyodo, arXiv:2507.22399 [hep-ph].

Speaker: Tomona Kinugawa (Tokyo Metropolitan University)

16:10 → 18:00 Parallel Session C: Hadrons from heavy-ion collisions 3

16:10 Low-energy K+N scattering revisited and in-medium strange quark condensate

It is important to investigate the in-medium quark condensates to understand the mechanism of the spontaneous breaking of chiral symmetry. The up and down quark condensates in nuclear medium are studied by pionic atoms and low energy pion nucleus scattering. It is found that the magnitude of the ud quark condensates may be reduced by 30% at the nuclear saturation density. This is known as partial restoration of chiral symmetry in nuclear medium. For a systematic study of partial restoration of chiral symmetry, it is interesting to see how the strange quark condensate behaves in nuclear matter. The chiral ward identity connects the in-medium quark condensate to the soft limit value of a correlation function of the pseudoscalar fields evaluated in nuclear medium. For the strange quark condensate, one considers the correlation function of the pseudoscalar fields with strangeness. The correlation function describes in-medium propagation of kaon and it is obtained phenomenologically by kaon-nucleon scattering in the low density approximation. In this talk we describe the kaon-nucleon scattering amplitude in chiral perturbation theory and its low energy constants are determined by existent $K^+N$ scattering data. Performing analytic continuation of the scattering amplitude obtained by chiral perturbation theory, we can take soft limit of the scattering amplitude. With this amplitude, we evaluate the in-medium strange quark condensate based on hadron phenomenology [1]. We also discuss $K^+d \to KNN$ scattering where we can extract $KN$ interaction at low energy [2].

[1] Y. Iizawa, D. Jido, S. Hübsch, Prog. Theo. Exp. Phys. 2024, 053D01 (2024),
[2] S. Hirama, D. Jido, in preparation

Speaker: Daisuke Jido (Institute of Science Tokyo)

16:30 Probing QCD matter from spin transport of hadrons in nuclear collisions

In relativistic heavy ion collisions, the collective behaviors of deconfined quarks and gluons characterized by the hadron spectra and flow reveal the formation of quark gluon plasma (QGP), which can be macroscopically described by relativistic hydrodynamics with the transport coefficients governed by the underlying strong interaction. Recent measurements of the global spin polarization of Lambda hyperons further indicate the presence of strong vorticity of the rotating QGP and manifest the relativistic Barnett effect at the subatomic scale. However, it is elusive how we could further explore the microscopic properties of a QCD medium through spin-related observables. Recently, the measured spin alignment phenomena of vector mesons cannot be simply explained by the vorticity, which may lead to such a new opportunity. Microscopically, a considerable number of soft gluons, in the QGP phase or even in the glasma phase as its precursor with overpopulated gluons in the color-glass-condensate effective theory, may be delineated by fluctuating chromo-electromagnetic fields (or color fields for short). We will discuss how such color fields may potentially result in the spin alignment through the anisotropic spin correlation of the quark and antiquark forming a vector meson via quark coalescence. Also, the pertinent effects from color-field correlators with anisotropic quark flow could give rise to local spin polarization of $\Lambda$ hyperons along the beam direction. Consequently, we may employ the spin transport phenomena to probe the microscopic interaction of QCD matter in high-energy nuclear collisions.

Speaker: Di-Lun Yang (Institute of Physics, Academia Sinica)

16:50 Matching nucleon structure to hydrodynamics

Motivated by the apparent hydrodynamic behavior in small systems, we discuss the problem of matching hydrodynamic initial conditions to nucleon structure.
Conceptually, this opens a puzzle, since hydrodynamics is a classical theory, and fluctuating hydrodynamics is a stochastic theory, but nucleon 3D structure is a deeply quantum object, with the ingredients necessary for hydrodynamics not simultaneusly measurable.
We discuss different objects encoding entropy and energy-momentum density, and formulate a recipe by which a hydrodynamic initial condition can in principle be constructed.

Speaker: Giorgio Torrieri

17:10 Measurement of differential cross section and spin-density matrix elements for backward K*(892) production in the (K-, p) reaction at 1.8 GeV/c

Backward production of K(892) in the $(K^-, p)$ reaction serves as a probe for understanding the underlying reaction mechanisms, particularly the contributions from hyperons such as $\Lambda$ and $\Sigma$ in the u-channel, in addition to the dominant t-channel contribution. High-precision and high-statistics measurements of differential cross-sections and spin-density matrix elements (SDMEs) are essential for a comprehensive understanding of K(892) production at this beam momentum. Moreover, the hadronic properties of the K*(892), including its mass and width, may be altered in nuclear matter due to the partial restoration of chiral symmetry. These effects can also be investigated in $(K^⁻, p)$ reactions using both proton and carbon targets.

K(892) → $K^0_S\pi⁻$ decays in $(K^⁻, p)$ reactions at 1.8 GeV/c were successfully reconstructed in the J-PARC E42 experiment using the HypTPC for precise tracking and particle identification in the backward kinematic range $(−1 < cos θ_{K*} < −0.7)$. Spin observables, including SDMEs, were measured in the K(892) rest frame with nearly complete angular coverage, providing sensitivity to polarization effects and reaction dynamics. This presentation will report preliminary results on the differential cross sections and SDMEs for K*(892) production.

Speaker: Sungwook Choi (Korea University)

17:25 A color-tracking transport model for hadron and jet suppression in high-energy nuclear collisions

Jet serves as a crucial probe of the Quark-Gluon Plasma (QGP) created in relativistic heavy-ion collisions. While significant efforts have been devoted to developing transport models of jet interactions with the QGP, a simultaneous description of hadron and jet suppression within a unified framework still remains a great challenge. Based on our Linear Boltzmann Transport (LBT) model, we develop a transport approach that tracks the color information of partons during their elastic and inelastic scatterings with the QGP for the first time. This allows us to pause the Pythia vacuum shower of energetic partons at the thermal scale of the QGP, switch to parton transport inside the QGP, and in the end return to Pythia vacuum shower and hadronization outside the color-deconfined medium. Within this new framework, we are able to simultaneously describe the nuclear modification of different species of hadrons and jets, including inclusive and heavy flavor hadrons, as well as inclusive, charged, and heavy flavor jets. Our study highlights the essential role of scales in parton interactions with the QGP, and constructs a consistent picture of jet and hadron suppression in high-energy nuclear collisions.

Speaker: Yichao Dang (Shandong University)

17:40 Momentum kick model with multiplicity dependence in pp collisions and p-Pb collisions .

The long-range near-side ridge phenomenon in two-particle correlation(∆φ-Δη) provides significant insights into the dynamics of the early stage of collisions, governed by strong interactions. Although the hydrodynamic model describes this ridge structure in heavy ion collisions, this could not offer the enough explanation that ridge phenomenon occurs in the small systems such as pp collisions and p-Pb collisions, where the density and temperature are not enough to generate a hydrodynamic medium. The Momentum Kick Model (MKM) explains this effect via high-momentum jet particles transferring momentum to medium partons, inducing collective motion and has been successful in reproducing the experimental results. In recent study, this MKM extends its application related to the multiplicity in pp collisions. It connects the average number of kicked partons with charged-particle multiplicity through the impact parameter. In this work, we further extend this relation to pPb collision. We analyze the recent experimental pPb LHC data to explain the ridge structures and compare two results from pp and p-Pb collisions.

Speaker: Hyeong-Woo Noh (Inha University (KR))

16:10 → 18:00 Parallel Session D: Structure of hadrons 3

16:10 Baryon Structure Across Scales: From Correlations and Exotics to the Partonic Landscape

Recent experimental progress has revealed complementary aspects of this structure across different energy regimes.
At low energies, studies of baryon-baryon interactions and short-range correlations, accessed for instance through femtoscopy and hadronic scattering, provide constraints on how baryons interact and cluster.
At intermediate energies, precision spectroscopy has uncovered exotic hadrons such as tetraquarks, pentaquarks, and hadronic molecules, offering new insights into multi-quark dynamics and the role of color forces beyond conventional baryons.
At high energies, the future Electron-Ion Collider (EIC) will open a new window into the partonic structure of baryons and nuclei, enabling three-dimensional imaging of quarks and gluons and their correlations.
By combining these approaches, we are moving toward an integrated picture of baryon structure, bridging scales from correlations in nuclei to the partonic landscape probed at the EIC.

Speaker: Taku Gunji (University of Tokyo (JP))

16:30 NRQCD Re-Confronts LHCb Data on Quarkonium Production within Jets

We compare LHCb measurements of J/ψ and ψ(2S) transverse momentum distributions within jets with QCD calculations, which may be crucial in understanding the quarkonium production mechanism. Our theoretical calculations are based on the fragmenting jet function formalism, while the nonperturbative formation of quarkonia is described by the nonrelativistic QCD factorization formalism. We include the newest refinements in the perturbative calculation including resummation of threshold and DGLAP logarithms. We find that the ψ(2S) data has the potential to discriminate between the different production mechanisms proposed in the literature.

Speaker: Yunlu Wang

16:45 Scale-anomaly-induced confining pressure in the pion and the nucleon on the light front form

In this study, we investigate the influence of the QCD scale anomaly on the internal pressure distributions of the pion and nucleon, based on the trace-traceless decomposition of the energy-momentum tensor. We use recently reported model-independent results for the gravitational form factors, together with our own calculations within a top-down holographic QCD approach, to evaluate the pressure distributions of the pion and nucleon in both the instant form and the light-front form. Our analysis shows that, in all cases, the scale anomaly predominantly generates negative confining pressure. This finding suggests that the phenomenon is a universal feature, independent of the type of hadron and the choice of form used in the analysis.

Speaker: Daisuke Fujii (Japan Atomic Energy Agency)

17:00 Calculation of Bbar_s and Lambda_b semileptonic decays in heavy quark effective theory to probe symmetry between anti-s quark and ud diquark

In baryonic systems, a diquark, which is a pair of quarks with strong correlations, can behave as a single effective constituent. This concept has been discussed since the early days of quark theory, and its properties and importance have been the subject of ongoing theoretical interest. In particular, recent studies have suggested a supersymmetry between the $ud$ diquark (a boson) and the $\bar{s}$ quark (a fermion), as they have similar masses (around 500 MeV), electric charges, and color charges when they are constituent quark of hadrons containing a heavy quark such as the $b$ quark [1].Accessing information about the quarks inside hadrons is crucial for understanding the interactions among quarks and their intrinsic properties. For this purpose, analyzing the properties and decay processes of hadrons is one of the most effective approaches to gain insight into the nature of constituent quarks.

In this work, we calculate three semileptonic weak decays of $b$ quark hadrons, $\bar B_s\rightarrow D_se\bar\nu_e$, $\bar B_s\rightarrow D_s^*e\bar\nu_e$, $\Lambda_b\rightarrow\Lambda_c e\bar\nu_e$, using Lorentz invariant form factors. According to Heavy Quark Effective Theory (HQET) and heavy quark symmetry, the form factors for the meson decays can be described by a single common function of heavy quark four-velocity, which is known as Isgur-Wise function $\xi(\omega)$. Similarly, the form factors for the baryon decay can be also expressed by another Isgur-Wise function $\xi'(\omega)$. We find that, under this assumption that $\xi=\xi'$, the decay rate of the baryon can be expressed in terms of the sum of the decay rates of the two mesons. This sum rule was found in Ref. [2] by assuming symmetry between $\bar s$ quark and $ud$ diquark in the heavy hadrons.

[1] T. Amano, D. Jido, PTEP2019, 093D02 (2019).

[2] T. Amano, D. Jido, S. Leupold, Phys. Rev. D105, L051504 (2022).

Speaker: KOHEI HASEGAWA (Institute of Science Tokyo)

17:15 Rapidity-Dependent Spin Decomposition of the Nucleon

The string-based formalism to Generalized Parton Distributions (GPDs) introduced in Phys.Rev.Lett. 133 (2024) 24, 241901 offers a unique opportunity to study the three-dimensional structure of the nucleon without any fine-tuning of parameters. Leveraging next-to-leading order PDF fits to parametrize the moments used in the conformal moment expansion of GPDs, the approach satisfies by construction all constraints from experimental data as well as Lorentz covariance, polynomiality and support constraints. In this talk I will discuss the recent extension of this formalism to axial and helicity flip GPDs discussed in 2507.18615 [hep-ph] to address the spin decomposition of the nucleon at finite skewness and, for the first time, present results on helicity singlet GPDs.

Speaker: Florian Hechenberger (Stony Brook University)

17:30 Electric and magnetic timelike form factors of hyperons at large transfer momentum

There has been considerable progress in the study of the electromagnetic form factors of baryons in the timelike region, through electron-positron scattering ($e^+ e^- \to B \bar B$ reactions), in the last two decades. Timelike experiments reveal information about the distribution of charge and magnetism inside the hyperons that cannot be obtained in spacelike experiments (electron scattering on baryons). Motivated by the novel data, we extend a covariant quark model that takes into account the meson cloud excitations of the baryon cores, developed for the spacelike region, to the timelike region, without any further parameter fitting. We use the formalism to calculate the electric ($G_E$) and magnetic ($G_M$) form factors of spin 1/2 baryons in the large square transfer momentum $q^2$ region. Our calculations are compared with the available data from CLEO and BESIII above $q^2=10$ GeV$^2$. We conclude that our predictions for the effective form factors(combination between $G_E$ and $G_M$) are in good agreement with the $q^2 > 15$ GeV$^2$ data for $\Lambda$, $\Sigma^+$ and $\Xi^-$. Our predictions can be further tested when large $q^2$ data for $\Sigma^0$, $\Sigma^-$ and $\Xi^-$ become available. We also compare our model calculations with the scarce available data for ratio $|G_E/G_M|$. We conclude that the present $q^2$ data range is not large enough to test our calculations, but that a more definitive test can be performed by upcoming data above $q^2=20$ GeV$^2$.

[1] G.~Ramalho, M.~T.~Pe\~na and K.~Tsushima,
"Hyperon electromagnetic timelike elastic form factors at large $q^2$,"
Phys. Rev. D \textbf{101}, 014014 (2020) [arXiv:1908.04864 [hep-ph]].

[2] G.~Ramalho, M.~T.~Pe\~na, K.~Tsushima and M.~K.~Cheoun,
"Electromagnetic $|G_E/G_M|$ ratios of hyperons at large timelike $q^2$,"
Phys. Lett. B \textbf{858}, 139060 (2024) [arXiv:2407.21397 [hep-ph]].

Speaker: Gilberto Ramalho (Soongsil University and OMEG Institute)

17:45 Effective field theory for radiative corrections to charged-current processes and hadronic uncertainty in neutral-current processes

We study radiative corrections to low-energy charged-current processes involving nucleons, such as neutron beta decay and (anti)neutrino-nucleon scattering within a top-down effective-field-theory approach. First, we match the Standard Model to the low-energy effective theory valid below the weak scale, specifying the scheme dependence of the Wilson coefficients. We evolve the resulting effective coupling down to the hadronic scale using renormalization group equations. To evaluate radiative corrections at scales of the neutron decay, we perform matching to heavy-baryon chiral perturbation theory and subsequently, below the pion-mass scale, to a pionless effective theory, evolving the effective couplings all the way down to the scale of the electron mass, relevant for beta decay. We provide a representation for hadronic corrections in terms of infrared finite convolutions of simple kernels with the single-nucleon matrix elements of time-ordered products of two and three quark bilinears (vector, axial-vector, and pseudoscalar). Using our new result for the radiative corrections, we update the extraction of the largest Cabibbo-Kobayashi-Maskawa matrix element Vud from the neutron decay.

I also refine the treatment of hadronic uncertainties in low-energy neutral-current processes, significantly reducing the current error estimate. These improvements have direct implications for all neutral-current interactions at low energies, including parity-violating electron scattering, elastic (anti)neutrino-electron scattering, coherent elastic (anti)neutrino-nucleus scattering, and atomic parity violation.

Speaker: Prof. Oleksandr Tomalak (Institute of Theoretical Physics)

18:30 → 20:30 Conference dinner

Friday 14 November

09:00 → 10:40 Plenary: Plenary 9

09:00 Hadron physics experiments with HypTPC at J-PARC

The Hadron Experimental Facility at J-PARC provides unique opportunities to explore hadron physics with high-intensity kaon, pion, and anti-proton beams. A series of experiments use the Hyperon Spectrometer equipped with a GEM-based Time Projection Chamber (HypTPC) operated in a 1-T superconducting magnet. In this talk, I will briefly introduce the experimental environment at the J-PARC Hadron Experimental Facility and outline the main features of the HypTPC. I will then highlight ongoing and planned experiments that exploit the capabilities of the HypTPC, with emphasis on the E45 experiment dedicated to N* spectroscopy.

Speaker: Shin Hyung Kim (Kyungpook National University (KR))

09:25 Nucleon and hyperon resonances

We have studied nucleon and hyperon resonances based on the experimental scattering data and lattice QCD simulations within Hamiltonian effective field theory. Some of them are very exotic, for example, the $\Lambda(1405)$ is mainly a $\bar K N$ molecule and the $N^*(1440)$ is dynamically generated. However, the traditional triquark states are still very important and exist in the excited baryons, for example, the $\Lambda(1670)$ contains the conventional quark model $\Lambda(1P)$. Pion photoproductions or electroproductions are also essential processes to further disclose the properties of nucleon and hyperon resonances, and we have also investigated their experimental and very recent lattice QCD data. By these combined analyses, both the coupled channels and the triquark bases play special roles in these low lying baryon resonances. Recent progresses of the related topics will be also reviewed in this report.

Speaker: Zhan-Wei Liu (Lanzhou University)

09:50 Coupled channel dynamics for baryon resonances from Lattice QCD

Progress in lattice QCD computations of coupled-channel
meson-baryon
scattering amplitudes is reviewed. Particular attention is given to the
first
coupled-channel computation of the Lambda(1405) system, which identifies
an additional resonance pole corresponding
to the Lambda(1380). Further prospects for other baryon resonances are
also discussed.

Speaker: John Bulava

10:15 New Progress on Nucleon-Nucleon Short Range Correlations

Short-Range Correlations (SRC) in nuclei arise when nucleons are forced into close proximity by the tensor part of the nuclear force and subsequently repelled by its short-range core. These correlations are key to understanding the underlying dynamics of nuclear forces and the properties of dense nuclear matter, such as neutron stars. They also provide crucial experimental input for exploring the quark structure of nuclei and the strong interaction within Quantum Chromodynamics (QCD).

Recent progress at Jefferson Lab has significantly advanced SRC studies through high-precision electron- and photon-scattering experiments, establishing a solid foundation for exploring their dynamics. Looking forward, new opportunities will emerge from ion–proton collisions in inverse kinematics at facilities such as GSI, JINR, HIRFL-CSR, and the upcoming High Intensity heavy-ion Accelerator Facility (HIAF) in China. These experiments will allow precise mapping of SRC kinematics, extend studies to radioactive isotopes, and enable searches for long-sought three-nucleon SRC signatures. Together, these efforts will open new avenues for probing the short-distance structure of nuclei and deepen our understanding of strong interactions in dense systems.

Speaker: Zhihong Ye (Tsinghua University)

10:40 → 11:10 Coffee break

11:10 → 12:25 Plenary: Plenary 10

11:35 Advances on Nucleon Structure from Lattice QCD

Understanding the internal structure of the nucleon remains a fundamental challenge in nuclear and particle physics. Lattice Quantum Chromodynamics (LQCD) provides a rigorous, first-principles framework to study key nucleon properties, including parton distributions, form factors, and moments of generalized parton distributions. Recent advancements in computational algorithms, renormalization techniques, and statistical precision have significantly improved our ability to extract nucleon observables with controlled systematic uncertainties.

In this talk, I will present recent progress in LQCD calculations of nucleon structure, highlighting results on the axial charge, electromagnetic form factors, and partonic distributions. I will discuss the role of novel approaches, such as large-momentum effective theory (LaMET) and pseudo-distributions, in accessing partonic structure directly from lattice simulations. Additionally, I will address challenges related to excited-state contamination, finite-volume effects, and discretization artifacts, and how they are being systematically controlled in state-of-the-art calculations.

Speaker: Simone Bacchio

12:00 Nucleon Structure Studies in Chiral Effective Theory

In recent years, laboratories around the world have conducted extensive measurements of the nucleon structures, in particular, to study generalized parton distribution functions (GPDs) of nucleon through processes of deep virtual Compton scattering and deep virtual meson production. We use the chiral effective field theory (EFT) to systematically investigate the various GPDs of nucleon and their corresponding generalized form factors. We note that the nonlocal effective theory can be applied to study physical quantities at relatively large momentum transfer compared with the traditional local chiral perturbation theory. We discuss the obtained GPDs and form factors of nucleon in nonlocal EFT which appear in good agreement with the experiments.

Speaker: Prof. Chueng-Ryong Ji (North Carolina State University)

12:25 → 14:00 Lunch

14:00 → 15:15 Plenary: Plenary 11

14:00 Status of the super-tau-charm factory

The proposed STCF is a symmetric electron-positron beam collider designed to provide e+e- interactions at a center of-mass energy from 2.0 to 7.0 GeV. The peaking luminosity is expected to be 0.5x10^35 cm-2s-1. STCF is expected to deliver more than 1 ab-1 of integrated luminosity per year. The huge samples could be used to study the spectroscopy, structure and decays of baryons, search for CP violation in (charmed-)baryons, measurement of the baryon form factors and CKM matrices, study the entanglement of hyperon-antihyperon and so on. In this talk, the physics interests will be introduced as well as the the recent progress on the project R&D.

Speaker: xiaolin Kang

14:25 Effective charges and evolution equations

We describe a novel approach for QCD evolution based on the notion of effective charges. This approach is applied to the evolution of parton distribution and fragmentation functions, and in particular, gravitational form factors. Therefore, results obtained at genuinely low momentum scales, relevant for continuum Schwinger methods, can be consistently evolved up to empirical scales, enabling direct comparison with experimental data.

Speaker: Prof. José Rodríguez-Quintero (University of Huelva)

14:50 Study of exotic nuclei and rare isotope physics activities in Korea

The study of exotic nuclei is essential for understanding the behavior of protons and neutrons in nuclei and for exploring the origin of the elements. The low-energy accelerator of the Rare Isotope Beam Facility called RAON in Korea successfully delivered a stable $^{40}$Ar beam for domestic users last year and is expected to provide additional stable and rare isotope beams in the near future. One of experimental facilities called KoBRA will play a central role in early-phase experiments on nuclear structure and nuclear astrophysics. The Center for Exotic Nuclear Studies (CENS) at the Institute for Basic Science (IBS) was established to perform experiments with both stable and rare isotope beams at leading international facilities such as RIKEN and FRIB, as well as at RAON. To support these efforts, CENS is actively developing advanced detector systems and experimental devices. This presentation will highlight recent research activities at CENS and provide a brief update on user experiments at RAON.

Speaker: Kevin Hahn

15:15 → 15:45 Coffee break

15:45 → 16:15 Plenary: Elsevier

15:45 Coffee break

16:15 → 17:50 Plenary: Closing