We provide an overview of the soft-photon puzzle, i.e., of the long-standing discrepancy between experimental data and predictions based on Low's soft-photon theorem, also referred to as "anomalous" soft photon production, and we review the current theoretical understanding of soft radiation and soft theorems. We discuss how both topics can be addressed with the planned ALICE 3 detector at the...
The gluon dominance model is developed to describe multiparticle production of secondary particles at high energies in lepton and hadron interactions, including annihilation processes and heavy quarkonium decays. According to this model, the multiparticle process is divided into two stages. The first stage describes the development of a quark-gluon cascade as a Markov branching process in the...
The Multi-Purpose Detector (MPD) is the dedicated heavy-ion experiment of the Nuclotron-based Ion Collider fAcility (NICA), at the Joint Institute for Nuclear Research (JINR). It will operate in the energy range of 4 GeV$\le \sqrt{s_{NN}} \le$ 11 GeV and will search for novel phenomena in the baryon-rich region of the QCD phase diagram. A primary objective of the MPD experiment is the search...
In the PMNS matrix, the relation $|U_{\mu i}| = |U_{\tau i}|$ (with $i = 1, 2, 3$) is currently favored by experimental data. This observation has sparked significant interest in the neutrino community due to its potential link to an underlying flavor symmetry. In this paper, we explore the implications of the condition $|U_{\mu i}| = |U_{\tau i}|$ within the framework of the canonical seesaw...
In our contribution, we will present recent theoretical developments designed to improve the modelling of quarkonia formation in ultrarelativistic heavy ions collisions as well as the systematic uncertainty resulting the semiclassical treatment which is often used in such situation. Accurate modeling and understanding of quarkonium production in such case requires a formalism that preserves...
Possible phase transition of strongly interacting matter from
hadron to a Quark Gluon Plasma (QGP) state have in the past considerable
interest. The clustering of color sources provides a framework of the partonic interactions in the initial stage of the collisions. The onset of de-confinement transition is identified by the spanning percolation cluster in 2D percolation.
The...
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...
Jet suppression has long been considered a signal for QGP formation in A-A nuclear collisions. Conventional approaches include a classical Glauber model to estimated number of nucleon participants Npart and N-N binary collisions Nbin. A spectrum ratio RAA incorporating Nbin and assuming hard-component (jet-related hadrons) factorization is intended to measure the extent of high-pt jet...
Recent CMS data revealed intriguing long-range correlations within high-multiplicity jets produced in proton-proton collisions, suggesting the potential onset of collective behavior, typically associated with heavy-ion collisions, at much smaller scales. Two-particle correlations in the “jet frame†show a surprising rise in elliptic flow harmonics, $v_{2}^*$, at large pseudorapidity...
In this talk, I discuss challenges in modelling collective expansion of baryon-rich medium in heavy-ion collisions at RHIC Beam Energy Scan or FAIR energies. Then I focus on specific approaches of multi-fluid dynamics and single-fluid dynamics with dynamical fluidization. I show generic conclusions from fluid-dynamic modelling at such energies, then present results from the two approaches and...
The study of nuclear structure has long been a fundamental aspect of nuclear physics, offering critical insights into the forces and interactions that govern matter at the subatomic level. Investigating nuclear structure in relation to complex nucleon-nucleon interactions poses significant challenges in low-energy nuclear physics, prompting extensive research into various phenomenological...
A hot and dense quark–gluon medium is observed to be created in ultrarelativistic nuclear collisions, exhibiting striking collective flow behavior, with fluid-like properties well described by relativistic hydrodynamics, with minimal viscous dissipation. The characteristics of this medium are under intense investigation, and in particular, its thermodynamical properties. In this context, the...
The new results on three-pion Bose-Einstein correlations measured with the sample of proton-proton collisions recorded at the centre-of-mass energy of √s = 7 TeV will be presented, being the first study of three-particle Bose-Einstein correlations measured in the forward region provided by the LHCb detector. The results are interpreted within the core-halo model for the first time in...
One of the most effective techniques for investigating the mechanism of baryon production is the study of angular correlations between two particles. Angular correlations represent a convolution of various physical processes, such as mini-jets, Bose-Einstein quantum statistics, conservation of momentum, resonances, and other phenomena that contribute to the unique behavior observed for...
Measure v2(pt) is interpreted to estimate the amplitude of an azimuth component of particle pt spectra arising from transverse (elliptic) flow of a dense QCD medium. Comparisons of v2 data with hydrodynamic (hydro) theory seem to indicate very low medium viscosity leading to attribution of a "perfect liquid." As defined v2(pt) is a ratio, with a single-particle spectrum appearing in its...
By smashing heavy nuclei at RHIC and the LHC and analysing the anisotropic expansion (flow) of the final state produced particles, unique information on the structure of the collided nuclei can be obtained. Existing efforts primarily focus on the colliding mode of heavy nuclei collisions. In contrast, nuclear structure studies with collisions of light nuclei and the fixed target mode have not...
Particle correlations are powerful tools for studying quantum chromodynamics in hadron collisions. In heavy-ion collisions, azimuthal angular correlations probe collective phenomena in hot, dense, nuclear media, such as QGP. In small collision systems, they could point to final-state effects or potential initial-state correlations. The LHCb experiment has the unique ability to study particle...
sPHENIX is a next-generation collider detector at RHIC, featuring large-acceptance calorimeters and precision tracking systems. The detector was successfully commissioned and collected physics data in both p+p and Au+Au collisions in 2024. Full-scale Au+Au data taking is currently in progress in 2025.
sPHENIX has excellent capabilities for measuring bulk particle production—such as the...
In high-energy heavy-ion collisions, a nearly perfect fluid is formed, known as the strongly coupled quark-gluon plasma (QGP). After a short thermalization period, the evolution of this medium can be described by the equations of relativistic hydrodynamics. As the system expands and cools, the QGP undergoes a transition into hadronic matter, marking the onset of quark confinement. Direct...
We present a detailed analysis of the nuclear modification factor $R_{AA}$ for charged particles produced in central Pb-Pb collisions at LHC energies, incorporating dynamical effects within a nonextensive framework. The study is based on a solution of the Plastino-Plastino Equation (PPE), a nonlinear Fokker-Planck-type equation that emerges naturally in the context of Tsallis nonextensive...
An utterly intense magnetic field is expected to be generated in non-central heavy-ion collisions. Despite intense effort during the last few years, a clear signal of this field has not yet been found.
We show that a very clear signal of the presence of a strong magnetic field during the early stage of a high-energy heavy-ion collision is provided by the decay of the 𝑍0 into dimuon pairs. We...
Jets — collimated sprays of particles from high-energy quarks and gluons— lose energy when traversing the quark--gluon plasma, a phenomenon known as \emph{jet quenching}. We develop an analytic framework that captures this process through a turbulent gluon cascade, driven by medium-induced splittings at all angles. A non-linear rate equation, amplified by the medium length $L$, connects to a...
Heavy-flavor hadrons, containing charm or bottom quarks, serve as sensitive probes of perturbative QCD across a wide range of energy scales and collision systems. Recent experimental advances have significantly deepened our understanding of heavy-flavor production mechanisms, hadronization dynamics, and interactions with nuclear matter. Notably, recent measurements in proton-proton (pp)...
Recent years have seen major progress in the study of exotic hadrons—particles that go beyond the traditional quark–antiquark or three-quark picture. This talk will present selected highlights from experiments at the LHC and other facilities worldwide, including new discoveries of tetraquark and pentaquark candidates, along with advances in understanding the properties of such states....
We report progress on the Heavy-Flavor Non-Relativistic Evolution (HF-NRevo) setup, a novel methodology to address the quarkonium formation within the fragmentation approximation. Our analysis addresses the moderate to large transverse-momentum regime, where the production mechanism based on the leading-twist collinear fragmentation from a single parton is expected to prevail over the...
In the realm of flavor changing processes can probe new physics (NP) at scales beyond the reach of current experiments, we analyze semileptonic decays of $B$, $B_s$ and $B_c$ mesons using \emph{Relativistic Independent Quark Model - a QCD inspired model} emphasizing the harmonic potential model-dependent analysis of heavy flavor dynamics. Our predicted branching fractions and physical...
Long-range multiparticle correlations as observed in the ultrarelativistic collisions of heavy ions at RHIC and the LHC has long been held as a signature of hydrodynamic flow in the novel phase of hot and dense matter known as the quark gluon plasma. However, these correlations, manifesting most simply as an elliptical Fourier coefficient or v$_{2}$, has subsequently been observed not just in...
We discuss recent extractions of both unpolarized and polarized quark TMD Parton Distribution Functions (TMD PDFs) in the proton, as well as TMD Fragmentation Functions (TMD FFs). These results are based on global fits of Drell–Yan and Semi-Inclusive Deep-Inelastic Scattering (SIDIS) data sets performed by the MAP collaboration. We also compare our findings with those from other groups,...
In this talk, I will present an analysis based on renormalon techniques in the large-beta0 limit to estimate leading non-perturbative power corrections relevant to collider observables. As a proof of concept, we apply this approach to e+e- collisions and successfully reproduce the leading non-perturbative corrections for observables sensitive to the invariant mass. Extending this framework, we...
In this talk, we discuss the recent progress in Lattice QCD extractions of partonic distributions of the nucleon. The focus of the talk are parton distribution functions (PDFs) as well as generalized parton distributions (GPDs), at leading twist and at twist-3. We review theoretical and practical advances in this field and present a selection of results obtained in the last years. Finally, we...
I will review the state-of-the-art determinations of parton distribution functions obtained with the inclusion of large-x and small-x logarithmic resummations in the theoretical predictions, and present future perspectives in this context.
Precision computations for standard candle processes are a staple of the physics programme at colliders such as the Large Hadron Collider (LHC). The highest precision can be achieved in perturbative computations. In perturbation theory, however, calculations truncated at a fixed order inevitably have inherent theoretical uncertainty. This uncertainty quantifies the contributions from the...
We study the properties of a system composed of strongly interacting matter with an isospin imbalance, using as an effective description of QCD the two-flavor Linear Sigma Model with quarks. From the one-loop effective
potential, including the two light quarks, pions and
sigma contributions, and enforcing the restrictions imposed by chiral symmetry, we show that the development of an isospin...
We present a comprehensive study of near-threshold structures in the J/\psi J/\psi mass spectrum using the fully reconstructed J/\psi J/\psi \rightarrow 4\mu final state, based on proton-proton collision data at \sqrt{s} = 13 and 13.6 TeV collected by the CMS experiment. With approximately four times more J/\psi pair candidates compared to the previous Run 2 dataset, the combined data sample...
The LHCb experiment is well suited to the spectroscopy of heavy flavor hadrons. The proton-proton collisions provided by the Large Hadron Collider produce a variety of heavy flavor states, and the excellent vertex and momentum resolution of the LHCb detector enables precision studies of hadron properties. Access to the kinematics of full decay chains allows amplitude analysis, which provides...
Multi-hadron reactions play a key role in several subfields of nuclear and particle physics, including hadron spectroscopy, nuclear reactions, and precision tests of the Standard Model of particle physics. Despite the non-perturbative nature of quantum chromodynamics (QCD), the advent of lattice QCD has enabled the direct constraint of various hadronic reactions from the Standard Model. In...
We review the theoretical foundations, methodological approaches and current status of the determination of nuclear parton distribution functions (PDFs). A large variety of measurements in fixed-target and collider experiments provide increasingly precise constraints on various aspects of nuclear PDFs, including shadowing, antishadowing, the EMC effect, Fermi motion, flavour separation,...
I will discuss progress in the theoretical treatment and modelling of multi-parton distibutions, focussing on the inclusion of various types of correlations beyond the simple “pocket formula” approach. Such distributions are needed for theoretical predictions of multiple parton scattering cross sections at the LHC. I will focus mainly on the case of double parton distributions, but will also...
Hadronization, the non-perturbative process through which quarks become color-neutral hadrons, remains a key challenge in QCD. Complementary insights into this process come from diverse experiments, including Drell-Yan, Heavy-Ion collisions, and Semi-Inclusive Deep-Inelastic Scattering (SIDIS).
This talk focuses on recent and ongoing SIDIS studies off nuclear targets, a program initiated...
Color deconfinement and chiral-symmetry restoration have long been predicted by QCD theory. Color deconfinement in the form of a nearly perfect fluid of quarks was reported by all four RHIC experiments in 2005. In a December 2024 paper, the PHENIX Collaboration details two-pion Lévy-stable Bose-Einstein correlation data in Au+Au collisions at the top RHIC energy and reports a significant...
In recent years, a number of charmonium-like states have been observed
above the open-charm threshold in various experiments. Their properties often go
against our expectations for regular charmonium states, making their
interpretation difficult. With BESIII, we are a leading contributor to the
experimental studies of the so-called XYZ states – studying Y-states directly in
e+e-...
In this talk I will present a relativistic formalism for three-particle scattering with arbitrary angular momentum, developed from the integral equations that can be used in lattice QCD analyses. Focusing on spinless systems, I present the partial-wave projected scattering amplitudes that preserve S-matrix unitarity and give simplified expressions for short-distance three-body interactions in...
The sexaquark is a stable state with quark content ( u u d d s s) hypothesized by [1] which might be a candidate for dark matter in the Universe. We present results [2] on the coalescence production of the sexaquark using the parton and hadron cascade model PACIAE in p+p collisions at sqrt(s) = 7 TeV. The yields, yield ratios, and dependences of the spatial parameters (the size of the diquark...
We will present a review of recent ultraperipheral collisions from the ATLAS and CMS results.
Ultra-peripheral collisions (UPCs) at the LHC offer a clean and controlled environment to study photon-induced interactions in the absence of hadronic interactions from collision with nuclear overlap. The ALICE experiment has established a comprehensive UPC physics program spanning QCD, electroweak, and nuclear structure studies.
The photoproduction of light vector mesons, such as...
We study exclusive $J/\Psi$,$\Upsilon$, and $c \bar{c}$, $b \bar{b}$ photoproduction for proton and Pb targets in the high-energy limit, with the energy dependence computed using the linear Balitsky-Fadin-Kuraev-Lipatov and the nonlinear Balitsky-Kovchegov evolution equations. The difference between these two evolution equations can be directly attributed to gluon saturation physics. We find...
In this talk we argue that geometric scaling conjectured and observed at
the ISR more than 50 years ago, still holds at the LHC. We discuss
regularities of the dip-bump structures of the differential elastic cross sections, emphasizing the fact that the ratio of bump to dip positions
is constant from the ISR to the LHC. Applying crossing and analyticity we
identify imaginary and real parts...
In July 2025, the LHC successfully carried out its first light-ion collision programme, delivering substantial luminosities for proton–oxygen, oxygen–oxygen, and neon–neon collisions across the LHC experiments. These new datasets offer unique opportunities to study the quark–gluon plasma in lighter nuclear systems and to explore the role of initial-state configurations in nuclear...
A+A collisions at BES RHIC energies were generated in UrQMD and SMASH MC Models and compared with results in the box with periodic boundary conditions.
The comparison of pt spectra of different particles with Boltzmann and Tsallis distributions at different time slices has been done.
Our study indicates that - Tsallis distribution better matches the particle pT –spectra both for the...
This talk will present a review of color glass condensate models, and also the phenomenology how to probe them using existing and incoming data.
In this talk, I will discuss the back-to-back limit of the DIS dijet production at next-to-eikonal accuracy computed in a highly boosted gluon background field within the Color Glass Condensate (CGC) framework.
I will show that the various types of next-to-eikonal corrections can be written as field strength insertions on the CGC Wilson lines which provide direct relation with the gluon...
We present a study of the central exclusive production (CEP) of $\eta$ and $\eta'(958)$ mesons in diffractive proton-proton collisions at high energies. The amplitudes, including pomeron and reggeon exchanges, are calculated within the tensor-pomeron model. Absorption effects are also taken into account at the amplitude level. We fit some undetermined model parameters (coupling constants and...
I present a feasibility study for measuring central exclusive $\eta,\eta' (958)$ production at the LHC. These pseudo-scalar mesons can be detected by their decays $\eta'(958) \rightarrow \pi^+\pi^-\eta$, and $\eta \rightarrow \pi^+\pi^-\pi^0$. For such measurements, the detection of the forward scattered protons is mandatory. I present the required detector position resolution of these very...
The LHCb experiment offers unique capabilities for studying ultra-peripheral collisions (UPCs) and other diffractive processes at the LHC. The forward acceptance of the detector, covering pseudorapidity $2<\eta<5$, allows for the detection of low-mass resonances produced in diffraction as well as kinematic reach down to very low $x$. The particle identification and vertexing capabilities of...
The origin and nature of cosmic rays in the EeV energy range remain one of the major open questions in astroparticle physics. Their energies far exceed those attainable by human-made accelerators, and their extremely low flux makes direct detection by space-based instruments unfeasible. For over two decades, the Pierre Auger Observatory—a 3000 km² array of instruments spread across the...
The measurement of hadronic interaction cross-sections at the highest cosmic-ray energies provides a unique opportunity to probe soft QCD processes beyond the reach of existing accelerator experiments. A key observable for such studies is the atmospheric depth at which air showers reach their maximum development ($X_\mathrm{max}$), which is sensitive to both the mass of the primary cosmic rays...
The search for origin of the most energetic cosmic rays has been mainly obscured by uncertainties in their mass composition arising from the modelling of hadronic interactions in the air showers that these particles induce. For some time now, discrepancies between the model predictions and measured air-shower data have been complicating efforts to find a consistent mass-composition scenario of...
This poster will present a feasibility study aimed at enhancing the reconstruction sensitivity for rare and \mbox{exhibits} heavy-flavour hadrons in Pb–Pb collisions in the \mbox{ALICE} experiment, using the $\Xi_{\mathrm{c}}^{+}$ baryon as a benchmark. The $\Xi_{\mathrm{c}}^{+} \rightarrow \Xi^{-} + \pi^{+} + \pi^{+}$ exhibits complex decay topology and low production rates, making its...
