A.T. D’yachenko$^{1,2}$
$^{1}$ National Research Center “Kurchatov Institute” B.P. Konstantinov Petersburg Nuclear Physics Institute, Gatchina, Russia;
$^{2}$ Emperor Alexander I Petersburg State Transport University, St. Petersburg, Russia
We managed to completely describe the spectra of cumulative protons, pions and photons for the collision of carbon nuclei with a beryllium target in the...
Bose–Einstein correlations of charged pions in Au+Au collisions at $\sqrt{s_{NN}}$ = 3 GeV from UrQMD
A. Kraeva${}^{1,2}$, G. Nigmatkulov${}^{1,2}$
E-mail: annakraeva555@gmail.com, nigmatkulov@gmail.com
The method of correlation femtoscopy makes it possible to estimate the parameters of the particle-emitting region (radius of emission region, $R$, and correlation strength, $\lambda$)....
Collisions of oxygen nuclei are planned in future LHC runs to scan the size of colliding systems at ultrarelativistic energies [1]. As shown by calculations [2,3], the admixture of the alpha-clustered states in O-16 leads to a triangular modulation of elliptic flow from the overlap region of colliding nuclei. The measurements [4] and modelling [5,6] of fragmentation of O-16 projectiles of...
Experimental results of ALICE collaboration on the emission of forward neutrons in ultraperipheral collisions of $^{208}$Pb nuclei at $\sqrt{s_{\mathrm{NN}}}=2.76$ and $5.02$ TeV are reviewed. Electromagnetic dissociation (EMD) events with the lowest multiplicity of 1, 2 or 3 neutrons dominate at both collision energies. The cross sections for 1n – 5n emission with and without protons were...
The HYDJET++ event generator is a phenomenological model of heavy-ion collisions that treats the collision process as a combination of a soft hydro-type state and a hard state resulting from hard parton scattering.
On the one hand, it allows one to quickly simulate relativistic heavy-ion
collisions, and on the other hand, it reproduces and describes a number
of experimental phenomena in the...
The data [1] on spectra of $K_S^0$ mesons measured by the STAR Collaboration in $\rm Au+Au$ collisions at various centralities characterized by different multiplicity densities of negative particles were analyzed in the $z$-scaling approach [2,3]. The transverse momentum distributions obtained in the BES-I program at RHIC were accumulated in seven centrality classes from the most central...
The helicity of quark-gluon medium is transmitted to spin polarization through axial anomaly. The possibilities of distinguishing of this mechanism, incorporating the recent data, from the thermodynamic one are discussed. The other manifestations of helicity, mimicking the chiral magnetic and vortical effects are also considered.
In high energy physics, software infrastructure for the analysis of experimental data is tightly connected with the specifics of experiment: detector setup, collision system, reconstructed event and track information. However, the aspects of physics analysis are common. In this work, we present a framework for correlation femtoscopy technique that could be applicable for any experiment.
It is...
The correlation between particles produced at various pesudorapidity values is an important probe to disentangle the underlying dynamics of multi-particle production in high energy collisions.
The long-range correlations are believed to be free from final-state effects.
The correlation strength ($b_{corr}$) has been studied for forward ($N_{F}$) and backward ($N_{B}$) charged partice...
The possible appearance of the effects of local parity breaking in the QCD medium formed in heavy ion collisions can happen due to violation of chiral symmetry, the difference between the average densities of right- and left-handed quarks in the fireball [1]. In the statistical approach, it can be quantified by corresponding chiral chemical potential $\mu_5$ [1,2]. The experimental...
We present results of simulations of the light-nuclei production in relativistic heavy-ion collisions within the updated event generator based on the three-fluid dynamics (3FD), complemented by Ultra-relativistic Quantum Molecular Dynamics (UrQMD) for the late stage of the nuclear collision~--- the Three-fluid Hydrodynamics-based Event Simulator Extended
by UrQMD final State interactions...
The model analysis of particle production in heavy ion collisions depending on number of emission sources (wounded nucleons or partons) at different centralities is performed in a wide collision energy range from RHIC to LHC and for all measured pair of heavy ions.
The model of wounded partons based on Glauber calculations gives better scaling for the ratio of charged particle multiplicity to...
The NA61/SHINE experiment at the CERN SPS has recently extended its program for the energy scan with Pb ions. In the past, the NA49 experiment, which preceded NA61/SHINE, also recorded data for Pb-Pb collisions at different energies. Together, the two experiments
cover a wide range of beam energies provided by the CERN SPS in the range 13 - 150 A GeV/c. Analysis of the new NA61/SHINE data and...
The results on the the vector Ay and tensor Ayy and Axx analyzing powers in deuteron-proton elastic scattering at large scattering angles are presented. These data were obtained at internal target at JINR Nuclotron in the energy range 400-1800 MeV using polarized deuteron beam from new polarized ion source. New data on the deuteron analyzing powers in the wide energy range demonstrate the...
Two particles angular correlations are a useful tool to study the mechanisms of particle production by observing the angular correlation (∆η,∆ϕ) between pairs of particles in an event. Different structures in the ∆η − ∆ϕ space are caused by various mechanisms of particle production and interactions between particles shortly after production. Examining these structures can give us insight
into...
Centrality is an important concept in the study of strongly interacting matter created in a heavy-ion collision whose evolution depends on its initial geometry. Experimentally collisions can be characterized by the measured multiplicities or energy of produced particles or spectator fragments. Relation between collision geometry and experimentally measured multiplicities is commonly evaluated...
Selection of the very recent results by the Compact Muon Solenoid (CMS) Collaboration on heavy-ion physics in relativistic collisions at LHC energies will be presented.
The invariant differential cross sections of inclusive $\pi^0$ and $\eta$ mesons were measured in the midrapidity region in pp collisions at $\sqrt{s}$ = 13 TeV and p--Pb collisions at $\sqrt{s_{NN}}$ = 8.16 TeV in a wide transverse momentum ($p_{\mathrm{T}}$) range with the ALICE experiment. The unprecedentedly large $p_{\mathrm{T}}$-range was achieved by combining various analysis techniques...
The deconfined state of strongly interacting quarks and gluons, quark-gluon plasma, may be formed in relativistic ion collisions at sufficient temperature and energy density. The signatures of quark-gluon plasma formation were observed in heavy-ion collisions by studying $\phi$ meson production. In small-collision systems, such as p+Al, p+Au, d+Au, and $^3$He+Au, the volume and lifetime...
ALICE-3 is being designed as a next-generation heavy-ion experiment to be operated at high-luminosity Large Hadron Collider (HL-LHC) at CERN after 2030. With a factor of fifty higher luminosity, the ALICE-3 will be able to study properties of quark-gluon matter with the probes, which were previously unavailable due to small cross-sections, high background levels, and insufficient sensitivity...
The study of the azimuthal anisotropy of hadron production provides the opportunity to investigate properties of nuclear matter at extreme energy densities, where quarks and gluons are deconfined. This state of matter was called quark-gluon plasma (QGP). The second order coefficient of azimuthal anisotropy, i.e. the elliptic flow ($v_{2}$), is one of the main observables measured in...
The future MPD experiment at NICA collider is designed to study heavy-ion collisions at $\sqrt{s_{NN}}$ = 4-11 GeV. For this energy range, which corresponds to the highest net-baryon densities and modest temperatures, models predict a first order phase transition from hadronic matter to the new state of matter formed of deconfined quarks and gluons and existence of a critical end point....
Particle Identification (PID) is an important part for most of the physics analysis in heavy-ion experiments. The principal challenge for PID is how to provide good identification in a wide range of particle momenta. Different approaches are used to combine observations from various detectors to enrich overall PID capabilities. Hence, PID is a classification task, that is why it can be...
In heavy-ion reactions, statistical models predict a rapid change in the baryon-to-meson ratio
as a function of the collision energy. This change occurs when the hadronic medium transits
from a baryon- to a meson-dominated gas. The transition is expected to take place at a
temperature of 140 MeV and a baryon chemical potential of 420 MeV, corresponding to a
collision energy of 8.2 GeV per...
