We analyze the effect of hydrodynamic fluctuations on normalized mixed harmonic cumulants (nMHC) based on a realistic dynamical model of the high-energy heavy-ion collisions for the first time.
The spacetime evolution of quark-gluon plasma (QGP) in high-energy heavy-ion collisions is described by hydrodynamics. The transport properties of QGP such as shear and bulk viscosity have been...
The sPHENIX experiment at Brookhaven National Laboratory (BNL) is a next-generation experiment equipped with a large solid angle detector to detect jets and precisely measure QGP properties. sPHENIX's INTT detector is a strip-type silicon detector that is positioned 7~10 cm from the collision point. The signal transmission cable of the INTT detector requires the development of a conversion...
J-PARC is one of the world’s highest-intensity proton accelerators for material and life sciences, neutrino physics, and hadron and nuclear physics in the GeV energy region. We are planning to accelerate world's high-intensity heavy-ion beams at J-PARC. We will build a new compact heavy-ion linac and a booster ring as an injector, while we utilize the existing RCS and MR synchrotrons to...
It is widely believed that gauge theories with fundamental matters exhibit a smooth connection between the confining and Higgs regimes. This Higgs-confinement continuity is of crucial importance to the quark-hadron continuity conjecture, which claims a smooth crossover between the nuclear superfluidity and color superconducting phases in dense QCD. Certain gauge theories with superfluidity,...
Hanbury Brown and Twiss (HBT) interferometry is used to investigate the shape and size of the matter produced in high-energy nuclear collisions. The Koonin-Pratt equation, which represents convolutions of the source function and the two-particle wave function in vacuum, has been used for the analysis. However, particles produced in a medium are affected during passing through it. In this talk,...
The Schwinger model (QED in one spatial dimension) is known as a toy model of QCD. We perform a Monte Carlo study of the Schwinger model at finite density. We circumvent the notorious sign problem by using the bosonization technique. We find that the number density is a smooth function of the chemical potential. This talk is based on arXiv:2303.05481 [hep-lat].
Recent measurements of the baryon-to-meson production yield ratios between charm baryons ($\Lambda_\mathrm{c}^{+}$, $\Sigma_\mathrm{c}^{0,++}$, $\Xi_\mathrm{c}^{0,+}$, $\Omega_\mathrm{c}^{0}$) and $\mathrm{D}$ mesons ($\mathrm{D}^0$) in small collision systems show a significant enhancement with respect to the measurements performed in $e^{+}e^{-}$ collisions. These results were compared with...
Quark-gluon plasma is a substance that scientists predict existed in the early universe according to Quantum Chromodynamics, and evidence for its existence is being discovered through both theory and experiment. Since QGP is in thermal equilibrium, researchers are studying its thermal properties to understand how it evolves over time. As the temperature rises, mesons separate into quarks and...
The studies of multi-strangeness hypernuclei help us further understand the interaction between hyperons and nucleons. This work discusses the productions of triple-baryons including $\Omega$, namely $\Omega NN$ and $\Omega\Omega N$, their decay channels and the baryon number dependence of productions. A variation method is used in calculations of bound states and binding energy of $\Omega NN$...
EIC stands for Electron-Ion Collider, a circular accelerator to be constructed at BNL, which is expected to discover new physics, such as those related to gluon condensation, by colliding electrons and nuclei.
In Japan, the EIC Japan group has been established and is active.
The Japan group has decided to proceed with the development of barrel TOF and is planning to use AC-LGAD in its...
The hyperon puzzle, namely the problem that hyperonic matter equations of state cannot support the observed massive neutron stars, has been attracting much attention. One of the proposed scenarios is that the $\Lambda$ particles do not appear even at high densities due to the repulsive $\Lambda$ potential at high densities generated by the $\Lambda$NN three-body force between the $\Lambda$...
We discuss anisotropic flow, or elliptic and triangular flow of charmonium states in heavy ion collisions using the coalescence model. Starting from the investigation on transverse momentum distributions of charmonia, we calculate elliptic and triangular flow of charmonium states produced at quark-hadron phase boundary by quark recombination. We argue that the wave function distribution plays...
During the Long Shutdown 3 (2026-2028) at LHC, ALICE is planning to replace the innermost three layers of the existing inner tracking system (ITS2) with a new silicon detector (ITS3) which is under development. ITS3 is based on truly cylindrical half barrels using wafer-scale monolithic active pixel sensors reducing the material budget and significantly. Thus, ITS3 will improve the trajectory...
The ALICE Collaboration is planning to install a new forward calorimeter (FoCal) as a detector upgrade to the ALICE experiment at LHC during the next long shutdown from 2027 to 2029. FoCal consists of the Si+W electromagnetic and conventional sampling hadronic subsystems (FoCal-E and FoCal-H, respectively), and it will cover the pseudorapidity interval of 3.4 < η < 5.8 at a place of 7 meters...
In non-central high-energy nuclear collision, very strong magnetic field is produced. High intensity magnetic field have never been directly detected experimentally, and we propose to measure virtual photon polarization as direct evidence. Since anisotropy appears in the lepton pair decay plane of a virtual photon polarized by a magnetic field, we aim to detect virtual photon polarization by...
Hadron interactions are important for understanding the hadron composite states such as exotic hadrons and hadronic nuclei. However natures of hadron interactions are still poorly understood. In recent years, lattice QCD analysis and measurements of correlation functions in heavy-ion collisions have provided information on the heavy hadron interactions.
In this work, we investigate the...
We investigate the effect of chiral symmetry restoration on dilepton invariant mass spectra measured in high-energy heavy-ion collisions. The hadron properties such as the hadron spectra change when the chiral symmetry restores in the hot medium created in high-energy heavy-ion collisions. We analyze the dilepton invariant mass spectra with hadron spectra obtained from different chiral...
The motivation of geometry engineering with p, d, and 3He projectiles at RHIC is to investigate the relation between initial geometry and final momentum anisotropy, which is thought to be strong evidence of QGP. PHENIX results show the elliptic and triangular flow hierarchy in p/d/3He+Au collisions follows the eccentricity described by the MC Glauber model. However, the initial geometry of...
We employ the AdS/CFT correspondence to study the jet quenching effect in Quark-gluon plasma in heavy-ion collisions.The nuclear modification factor $R_{AA}$ and elliptic flow parameter $v_{2}$ are studied in different-centrality collisions at RHIC and LHC.Our numerical results agree with data.Magnetic field and chemical potential of the medium are also considered for the observable...
In this study, we present the model study of the charged-particle multiplicity density, dNch/dη in Pb-Pb collisions at a centre-of-mass energy per nucleon-nucleon pair of $\sqrt{s_\mathrm{NN}}$ = 5.36 TeV. The centre-of-mass energy for Pb-Pb collisions is the highest ever that is planned to be collected by LHC at the end of 2022 for the first time. The multiplicity of charged particles...
Jet quenching is an important probe to quark-gluon plasma created in high-energy heavy-ion collisions. A significant parameter is known as jet transport coefficient $\hat{q}$ for jet eneygy loss, characterizing the interaction between the parton jet and medium. We study nuclear modification factors of hadron at large $p_T$ in central $A+A$ collisions in a NLO pQCD parton model in which parton...
We show that the topological charge of nonabelian gauge theory is not observable. We then inspect the phenomenological consequences to hadron physics and experiments such as the physical relevance of the axial U(1) symmetry and the unobservability of the chiral magnetic effect.
Strong electromagnetic (EM) field in heavy-ion collisions could leave an imprint on the final-state particles. Due to such EM field, particles and anti-particles with opposite charges will receive opposite contributions to their rapidity-odd directed flow. Here, we present the charge-dependent measurements of $dv_1/d\mathsf{y}$ near midrapidity for $\pi^{\pm}$, $K^{\pm}$, and $p(\bar{p})$ in...
We derive the chiral kinetic equation in 8 dimensional phase space in non- Abelian SU(N) gauge field within the Wigner function formalism. By using the “covariant gradient expansion”, we disentangle the Wigner equations in four-vector space up to the first order and find that only the time-like component of the chiral Wigner function is independent. After color decomposition, we present the...
In relativistic heavy-ion collisions, a hot and dense medium called QGP is created. Intriguingly, the collective motion of produced particles, which is thought to be evidence of the formation of strongly interacting QGP, has also been observed in high-multiplicity events of small systems like $pp$ and $p$--Pb collisions. In addition, studying the flow of identified particles with different...
A new detector was installed in ALICE in the forward region during LHC LS2 with the aim to improve the accuracy of the dimuon opening angle measurement more than ever since the LHC Run 3. Such new detector cannot identify muons and measure their momentum, so it must be used in combination with an existing detector. Therefore, it is necessary to correctly match the tracks reconstructed by...
Fluctuations of harmonic flow along pseudorapidity $\eta$, known as flow decorrelations, is an important probe of the initial condition and final state evolution of the quark-gluon plasma. We show that the flow decorrelations are sensitive to the deformations of the colliding nuclei. This sensitivity is revealed clearly by comparing flow decorrelations between collisions of isobars,...
Jet shape is studied with a linear Boltzmann transport model for event-by-event simulations of photon-tagged jets in heavy-ion collisions. The transverse momentum asymmetry $A_{\perp}$ is shown to increase with the initial transverse position when the gradient of jet transport coefficient $\hat{q}$ increases until at the edge of the nonuniform medium. On one hand,the shape of the photon-tagged...
The fragmentation of partons is studied using the jet fragmentation transverse momentum, j_{T}. The j_{T} is defined as the perpendicular component of the momentum of the constituent particle with respect to reconstructed jet momentum, \vec{p}_{jet}. The jT provides a measurement of the transverse momentum spread of the jet fragments. Recently, the direct dead-cone effect was measured by ALICE...
We explore the system size dependence of heavy-quark-QGP interaction by studying the HF meson suppression and elliptic flow in four different collisions at the LHC. Within an advanced Langevin-hydrodynamics framework, we provides a reasonable description of the D meson RAA and v2 in Pb-Pb collisions, as well as predictions for both D and B meson observables in other collision systems yet to be...
ALICE3, the next-generation heavy-ion experiment, has been proposed for the LHC RUN 5 and 6 to investigate the Quark Gluon Plasma properties, exploiting precise measurements of heavy-flavour probes as well as electromagnetic radiation. These measurements require excellent particle identification (PID) capabilities in a wide transverse momentum range.
The development of a Ring Imaging...
Vorticities in heavy-ion collisions (HIC) are supposed to induce spin alignment and polarization phenomena of quarks and mesons. In this paper, we consider a uniformly rotating medium in which quark and anti-quark pairing are suppressed. Consequently, in the framework of Nambu-Jona-Lasinio (NJL) model, dynamical quark masses are descending as the angular velocities grow. In case of vector...
Jets provide unique and powerful probes to study Quantum Chromodynamics in proton-proton collisions and the quark-gluon plasma medium in heavy-ion collisions. Among these probes, measurement of jet substructure and of the distribution of hadronic constituents within a jet provide a detailed look into the partonic shower process. ALICE has recently measured and published transverse momentum...
By means of real-time hard thermal loop resummed technique combined with dimension two gluon condensate, we (non-)perturbatively study how the strong magnetic field induced by colliding nuclei affects both heavy quark (HQ) potential and HQ momentum diffusion coefficient in the QGP. We show that HQ momentum diffusion coefficients become anisotropic, and with increasing temperature, the higher...
We derive the chiral kinetic equation in 8 dimensional phase space in non- Abelian SU(N) gauge field within the Wigner function formalism. By using the “covariant gradient expansion”, we disentangle the Wigner equations in four-vector space up to the first order and find that only the time-like component of the chiral Wigner function is independent. By color decomposition, we present the...
High-energy partons generated in relativistic particle collisions create well-collimated showers of particles, which are called jets. The jet study is used widely in heavy-ion collisions, where the quark-gluon plasma (QGP) medium forms. Previous studies from RHIC and LHC indicate that dijet invariant mass can be sensitive to modifications caused by the QGP medium. In this study, we present a...
Experimentally observed splitting of directed flow ($v_1$) between proton and anti-proton has been a challenging observable for the models to describe. We propose a two-component baryon deposition scheme driven by participants as well as binary collision sources. Evolving such a profile through a hybrid framework (hydrodynamics + hadronic transport), we are able to capture the $v_1$ of light...
Extremely large angular orbital momentum can be produced in non-central heavy-ion collisions,leading to a strong transverse polarization of partons that scatter through the QGP due to spin-orbital coupling.We develop a perturbative approach to describe the formation and spacetime evolution of quark polarization inside the QGP.Polarization from both the initial hard scatterings and interactions...
The short-lived resonances are sensitive probes of the hadronic phase whose lifetime is several fm/$c$ in heavy-ion collisions. The final state yields are expected to be affected by re-scattering and regeneration after chemical freeze-out. The measured yield of resonances tends to be suppressed by the re-scattering of daughter particles with other hadrons. On the other hand, it tends to be...
Heavy flavor jets are powerful tools to gain insight into the in-medium partonic energy loss mechanisms and the transport properties of the quark-gluon plasma (QGP) in high-energy nuclear collisions. In this work, we present the first theoretical study of the longitudinal momentum fraction $z_{||}$ carried by $\rm{D^0}$ meson in jets in Pb+Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV. The...
We are developing a Forward Calorimeter (FoCal) as one of the proposed ALICE upgrade projects at CERN. The FoCal extends the scope of ALICE, which was designed for the comprehensive study of hot and dense partonic matter, by adding new capabilities to explore the small-x region in parton distribution for nucleons and nuclei.
The electromagnetic calorimeter (FoCal-E) equipped with 18 pad...
Using a (3+1)-D hybrid framework with parametric initial conditions, we study $v_1(y)$ of identified particles, including pions, kaons, protons, and lambdas, in Au+Au collisions performed at $\sqrt{s}$ ranging from 7.7 to 200 GeV. The dynamics in the beam direction is constrained using the measured pseudo-rapidity distribution of charged particles and the net proton rapidity distribution....
We study the first-order Fox-Wolfram moment $H_1^T$ in relativistic heavy-ion collisions, where jet productions in p + p are simulated within a Monte Carlo event generator SHERPA 2.2.11, and the jet propagation in medium with the Linear Boltzmann Transport (LBT) model. Because of jet quenching effect, a suppression of the distribution at small $H_1^T$ region and an enhancement at large $H_1^T$...
Initial state fluctuations and final state anistropic flows have provided powerful tools for studying the evolution dynamics and transport properties of quark-gluon plasma produced in relativistic heavy-ion collisions. The quantitative research on anisotropic flow fluctuations may provide a unique potential to constrain the initial state models of heavy-ion collisions.
In this talk, we...
Numerical hydrodynamics is an indispensable tool to describe the dynamics of relativistic heavy-ion reactions. Its stability is usually difficult to handle, especially in fluctuating hydrodynamics. We develop a stable implicit numerical method for solving relativistic hydrodynamics that can be more efficient than conventional explicit methods. Implicit methods are desirable considering their...
We have investigated the charge-dependent anisotropic flow in high-energy heavy-ion collisions, using relativistic resistive magneto-hydrodynamics (RRMHD).
First, we construct a relativistic resistive magneto-hydrodynamic (RRMHD) numerical simulation code for high-energy heavy-ion collisions. We confirm that our code reproduces well the results of standard RRMHD tests in the Cartesian...
The Ridge behavior in high-multiplicity pp collisions has been discussed a lot since it was first reported in year. Because small systems cannot provide sufficient conditions to produce a medium called QGP, in which the ridge behavior is understood with hydrodynamics. In this work, we propose the pure kinematic mechanism between jets and medium partons as tools for describing the Ridge...
The strong electromagnetic field generated by the colliding nuclei in heavy-ion collisions can be represented by a spectrum of photons leading to photon-induced interactions. While such interactions are traditionally studied in ultra-peripheral collisions (UPC), significant enhancements of dilepton pairs and J/$\psi$ production at very low transverse momentum ($p_{\rm T}$) above the expected...
Since phenomena induced by the hydrodynamic fluctuations include the information of transport coefficients, the study of fluctuations could open up a new way of diagnosing the QGP precisely. We derive equations of motion (EoM) of hydrodynamic fluctuations by considering the perturbative expansion of energy-momentum tensor around the Bjorken's boost invariant solution. These EoMs are derived...
Relativistic hydrodynamics has been successful in describing space-time evolution of matter created in high-energy nuclear collisions. One conventionally assumes that created matter becomes fluids all at once at a certain initial time. It is, however, not at all trivial from which stage after the collision the fluid picture can be applied. Whether non-linear hydrodynamic equations obey the...
In April of this year, the sPHENIX experiment began at Brookhaven National Laboratory (BNL) in the United States, measuring the properties of a quark-gluon plasma (QGP) state created by colliding gold atoms accelerated by the Relativistic Heavy Ion Collider (RHIC). The sPHENIX Japan group (Nara Women's University, Rikkyo University, and RIKEN) is responsible for developing and constructing the...
Measurements of weak bosons, W$^{\pm}$ and Z$^{0}$, are powerful tools to study quantum chromodynamics (QCD). Due to their large masses, they are predominantly produced via quark-antiquark annihilation in the early stage of pp and heavy-ion collisions. Therefore, their production can be described by the perturbative QCD (pQCD) and is sensitive to the parton distribution function in nucleon and...
We carry out the first theoretical investigation on yields and the hardest parton splitting of large-radius jets reclustered from small radius ($R=0.2$) anti-$k_t$ jets in Pb+Pb collisions, and confront them with the recent ATLAS measurements.
The Linear Boltzmann Transport (LBT) model is employed for jet propagation and jet-induced medium excitation in the hot-dense medium. We demonstrate...
We study how the dilepton production rate (DPR) and the associated transport coefficients, the electric conductivity and relaxation time, are affected by the soft modes of the QCD critical point (CP) and the color superconducting (CSC) phase transition. We examine the modification of the photon self-energy by the so-called Aslamazov-Larkin, Maki-Thompson, and Density of States terms on the...
The production of quarkonia in high-energy heavy-ion collisions has been studied extensively to understand their production mechanisms and properties of QGP. Recent PHENIX studies show that the increasing J/ψ yields versus multiplicity in p+p collisions are similar to results in different J/ψ acceptance and collision energy, implying that MPI contributes to J/ψ production at RHIC energy. The...
Neuron, the basic unit of nerve cells, transmits stimuli by sending neurotransmitters to other neurons when receiving signals above the threshold. The algebraic structure that mimics this process is called perceptron, the basic unit of the artificial neural network (ANN). The ANN is used to solve problems in many fields of data processing such as classification, and is a useful tool,...
The origin of hadron masses cannot be attributed to the Higgs mechanism alone. On top of that, spontaneous breaking of chiral symmetry, potentially restored at extremely high temperatures, should play an important role. Light vector mesons (ρ, ω, φ) are highly sensitive to chiral symmetry restoration, so that a modification in their mass is expected. This study evaluates the detectability of ω...
We investigate the flavor dependent jet quenching, by performing a systematic analysis of medium modifications of the inclusive jet, $\gamma$-jet, and $b$-jet in Pb+Pb collisions relative to those in pp at the LHC. Our results from MadGraph+PYTHIA and LBT well describe the experimental data of the inclusive jet, $\gamma$-jet and $b$-jet both in pp and AA collisions simultaneously. We then use...
Recently, experimental measurements of the energy-momentum tensor (EMT) distribution inside hadrons receive attentions their theoretical investigations are becoming increasingly important. In this presentation, focusing on localized structures in quantum field theory, we calculate the one-loop correction to the distribution of EMT around a kink in 1 + 1 dimensional $\phi^4$ model and...
The precise knowledge of hyperon-hyperon interaction is one of the key measurements in QCD. To achieve this goal, it is fundamental to identify hyperons with a high purity in a high charged-particle multiplicity environment, such as a central Pb-Pb collisions. Thanks to its excellent particle identification and tracking performance, the ALICE experiment at the LHC is ideal for these...
The quark-gluon plasma(QGP) is considered the state of the early universe. The azimuthal anisotropy for charmonium states has been researched as one of the probes to understand the nature of the QGP. In this presentation, we will report recent progress regarding the study of the elliptic and triangular flow for prompt and nonprompt $\rm{J}/\psi$ and prompt $\psi$(2S) states in lead-lead...
Study of a chiral symmetry in QCD attract wide interests to study the QCD phase diagram. It is theoretically predicted that the chiral symmetry is partially restored at a finite density matter and it can be observed as modifications of vector meson mass spectra. An experiment is being performed at J-PARC to measure mass modifications of vector mesons in a nucleus, which can be considered as a...
The upgrades for Run 3 of the CMS experiment at LHC improves both hardware and software, resulting in the enhancement of detection efficiency and data streaming capabilities for the accumulation of the physics data. In this poster, we will introduce the latest strategy of the muon trigger for the Run3 heavy-ion experiment. It employs the newly developed algorithms to increase the trigger...
FAZIA (Forward A and Z Identification Array) is designed to identify charges and masses of reaction products from heavy-ion collisions from a few tens of MeV to about a hundred MeV per nucleon.
One basic unit of FAZIA consists of 4 x 4 shaped, three-layered telescopes.
The first and second layers are silicon sensors with different thicknesses of 300 um and 500 um, respectively, and one CsI...
Heavy quarks, produced in hard-scattering processes in the very early stage of heavy-ion collisions, are efficient probes of the quark-gluon plasma (QGP) properties through its full evolution. They subsequently decay into particles such as muons and electrons. In ALICE, at LHC energies, muons are detected by the forward muon spectrometer and the Muon Forward Tracker (MFT). Full simulations...
The thermalization and chemical equilibration processes of the gluon dominated matter produced immediately after high energy collision are still poorly understood due to its far-from equilibrium nature. We use transport simulation to explore this phase where we include 2-to-3 interactions which are important to the thermal and chemical equilibration processes as the source of particle and...
