Conveners
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics
- Evgeny Andronov (St Petersburg State University (RU))
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics: Flow
- Vladislav Sandul (St Petersburg State University (RU))
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics
- Igor Altsybeev (St Petersburg State University (RU))
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics: QCD; theory
- Daria Prokhorova (St Petersburg State University (RU))
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics: Centrality, BM@N/NICA physics
- Valerii Kondratev (Saint-Peresburg State University)
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics: Higgs physics
- Andrey Seryakov (St Petersburg State University (RU))
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics: LF,CF
- Evgeny Andronov (St Petersburg State University (RU))
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics: LHC
- Igor Altsybeev (St Petersburg State University (RU))
Section 4. Relativistic nuclear physics, elementary particle physics and high-energy physics
- Vladimir Kovalenko (St Petersburg State University (RU))
We report a new measurement of proton directed flow $v_1$ relative to the spectator plane for Ag+Ag collisions at the beam energies of 1.23A and 1.58A GeV recorded by the HADES experiment at GSI. The projectile spectator plane is estimated using signals of the charged fragments registered with the HADES forward hodoscope. Directed flow is presented differentially as a function of transverse...
Investigation of the reactions of deuteron elastic scattering and deuteron breakup are interesting from the point of view of nucleon-nucleon (NN) and three nucleon (3N) correlations, special attention is paid to short distances with high transferred momenta. The Deuteron Spin Structure (DSS) collaboration revealed a strong sensitivity to the spin structure of short-range isoscalar NN...
Author: Alexey Povarov (for the STAR Collaboration)
National Research Nuclear University MEPhI (NRNU MEPhI)
Heavy-ion collisions create matter which is characterized by high temperature and energy density, called Quark-Gluon Plasma (QGP). Azimuthal anisotropy of produced particles is sensitive to the transport properties of QGP (the equation of state, speed of sound and specific shear...
The analysis of charge distribution (Fig. 1) of intermediate mass fragments (IMF) was performed for interaction of 22 GeV carbon projectiles with a gold terget. The main behavior of charge distribution is well described by a power low with a power function exponent equal to 2.16 $\pm$ 0.03. The power law distribution follows from the classical droplet Fisher model [1], which predicts this...
The e$^+$e$^-$$\rightarrow$ $\text{n} \bar{\text{n}}$ cross section has been measured in the experiment at the VEPP-2000 e$^+$e$^-$ collider with the SND detector. The technique of the time measurements in the multichannel NaI(Tl) electromagnetic calorimeter is used to select n anti-n events. The value of the measured cross section from the threshold up to 2 GeV varies from 0.6 to 0.4...
In heavy-ion collisions, a strong magnetic field ($\sim$ 10$^{15}$ T) is expected to be created, which together with the presence of a non-zero electric and axial charge density, can lead to vector and axial currents in the produced system called the Chiral Magnetic Effect (CME) and Chiral Separation Effect (CSE), respectively. Their coupling gives rise to a collective excitation in the...
Short-range correlated (SRC) NN pairs play an important role in structure of atomic nuclei and are studied using mainly electron beams [1]. A new step was done at BM@N in JINR [2] where the reaction $^{12}$C+p→$^{10}$A+pp+N is studied using the $^{12}$C beam at energy of 4 GeV/nucleon in inverse kinematics providing interaction with the hydrogen target to probe the SRC pairs in the...
Anisotropic flow measurements of produced particles in relativistic heavy-ion collisions play an essential role in the studies of transport properties of the strongly interacting metter.
In this work we provide the results of the most comprehensive systematic study of the beam energy dependence of anisotropic flow based on existing data and discuss them using different scaling relationsfor...
Multi-Purpose Detector (MPD) experiment at NICA collider has the potential for discoveries in the area of QCD phase diagram with high net baryon densities and moderate temperatures. Anisotropic transverse flow is one of the key observables to study the properties of matter created in heavy-ion collisions. The directed and elliptic flow were studied at the beam energy range $\sqrt{s_{NN}}$=2-11...
Started in the late 1950s at DLNP JINR pioneering experimental studies of proton scattering on nuclei allowed D.I. Blokhintsev assumed the presence in nuclei a lower mass nucleus in a compressed state, i.e. the presence of a cold strongly compressed component in ordinary nuclear matter. The search and study of two- and three-nucleon systems in nuclei continued at DLNP JINR and ITEP (Moscow)...
The possibility to register the associated pair production of hadrons and light nuclei in a kinematically forbidden region in AA-interactions on the FODS double arm spectrometer at the U-70 accelerator complex (Protvino) is analyzed. The value of ion beam energy is 20.5 GeV/nucleon ($\sqrt{s_{NN}}$=6.3 GeV). The mode of measurements with one arm makes it possible to study production of hadrons...
The Compressed Baryonic Matter experiment (CBM) at FAIR aims to study the area of the QCD phase diagram at high net baryon densities and moderate temperatures using collisions of heavy ions at center-of-mass energies of a few GeV per nucleon. Anisotropic transverse flow is among the key observables to study the properties of matter created in such collisions. The CBM performance for charged...
Oleksii Lubynets $^{(1, 2)}$ and Ilya Selyuzhenkov $^{(1, 3)}$ for the CBM Collaboration
$^{(1)}$ GSI, Darmstadt, Germany
$^{(2)}$ Goethe Universität Frankfurt, Frankfurt am Main, Germany
$^{(3)}$ NRNU MEPhI, Moscow, Russia
The main goal of the CBM experiment is to study highly compressed baryonic matter
produced in collisions of heavy ions. The SIS-100 accelerator at FAIR will...
$\bf{A.T. D’yachenko^{1,2}, I.A. Mitropolsky^{2}}$
$^{1}$Emperor Alexander I Petersburg State Transport University, St. Petersburg, Russia
$^{2}$ B.P. Konstantinov Petersburg Nuclear Physics Institute, NRC “Kurchatov Institute”, Gatchina, Russia
On the basis of the hydrodynamic approach with a nonequilibrium equation of state [1-3], collisions with a beryllium target of $^{12}$C nuclei...
Recently the NA61/SHINE collaboration has published new experimental data on Pi- meson production in Ar-40+Sc-45 interactions at projectile nucleus laboratory momenta 13, 19, 30, 40, 75 and 150 GeV/c/N. The data are analyzed in Epos LHC, Epos 1.99 and Geant4 FTF models. The data were obtained for 0 - 5 % centrality interactions. In order to imitate the centrality selection we choose impact...
The main aim of the MPD experiment at the future collider NICA is to study the strongly interacting matter created in the heavy-ion collisions at center-of-mass energies $\sqrt{s_{NN}}$ = 4-11 GeV. The azimuthal anisotropy is a key observable in such collisions as its sensitivity to the transport properties and equation of state of the created matter. The relative elliptic flow fluctuations...
In the past years, significant progress has happened in high-energy nuclear physics models. A more robust and quantitative picture has replaced the qualitative descriptions of heavy nuclei collisions in the earlier days, enabling us to have a clearer picture of different stages of a heavy-ion collision. These models typically have $O(10)$ free parameters that are tuned by Bayesian analysis in...
The concepts of "scaling" and "universality" have been developed to study critical phenomena. Scaling implies that systems near a critical point (CP) exhibit self-similarity and are invariant with respect to scale transformations. The universality of their behavior lies in the fact that vastly different systems behave in a similar way near the respective CP.
We present some results of...
In the events of peripheral dissociation of relativistic nuclei in the nuclear track emulsion, it is possible to study the emerging ensembles of He and H nuclei, including those from decays of the unstable $^{8}$Be and $^{9}$B nuclei, as well as the Hoyle state. These extremely short-lived states are identified by invariant masses calculated from the angles in 2$\alpha$-pairs, 2$\alpha p$- and...
One of the methods for studying the transport properties of QCD matter at extreme temperatures and energy densities is the study of anisotropic flow. The precise definition of centrality is an important task since directed and elliptic flow coefficients are dependent on centrality. Two methods of centrality determination were considered to study the effect of different centrality determination...
It is well-established that high-multiplicity pp and p–Pb collisions exhibit a collective-like behaviour and signatures, like the strangeness enhancement and the ridge behaviors, that were commonly attributed to the formation of the Quark-Gluon Plasma. These processes, which are typically described by phenomenological models and soft QCD measurements, provide important constraints on the model...
This talk gives an overview of the latest measurements of collective behavior in a variety of collision systems with the ATLAS detector at the LHC, including pp collisions at 13 TeV, Xe+Xe collisions at 5.44 TeV, and Pb+Pb collisions at 5.02 TeV. These include measurements of vn-[pT] correlations in Xe+Xe and Pb+Pb, which carry important information about the initial-state geometry of the...
The hot dense matter produced in non-central heavy-ion collisions possess a large initial orbital angular momentum. This initial orbital angular momentum leads to global polarization of hadrons produced after hadronization, which could be measured via CP-violating weak decays of hyperons.
The STAR experiment observed non-zero $\Lambda$ global polarization. Large amount of new data provided...
This talk gives an overview of the latest hard process measurements in heavy ion collision systems with the ATLAS detector at the LHC, utilizing the high statistics 5.02 TeV Pb+Pb data collected in 2018. These include multiple measurements of jet production and structure, which probe the dynamics of the hot, dense Quark-Gluon Plasma formed in relativistic nucleus-nucleus collisions;...
Jet substructure measurements, based on the distribution of constituents within a jet, are able to probe specific regions of QCD radiation phase space for jet showers in vacuum. This powerful capability provides new opportunities to study fragmentation patterns of parton showers in vacuum and the dynamics of jet quenching in heavy-ion collisions.
The ALICE experiment has unique capabilities...
The investigation of nuclear matter effects in relativistic ion collisions, especially quark-gluon plasma (QGP) ones, is one of the main goals of PHENIX experiment [1]. To study the dynamics of collisions at high energies, strange hadron production is considered as a significant tool. Due to its strange quark content, the $K^{*0}$ meson is a good probe for the investigation of such QGP effects...
Measurement of charged hadron production in relativistic ion collision systems is one of the main methods to study hadronization of quark gluon plasma (QGP) - a state of matter, which is thought to consist of asymptotically free quarks and gluons [1]. According to QCD calculations, conditions in small collision systems are not sufficient for QGP formation, but flow studies in the PHENIX...
Precise study of heavy ion collisions in the energy range $\sqrt{s_{NN}}$ = 4 - 11 GeV is one of the key features of the NICA complex which is currently under construction at JINR (Dubna). Current experimental results in this area suggest this energy region as the most interesting to study the QCD phase diagram and search for phase transition and possible Critical Point. The MPD experiment at...
The $p_T$ distributions of the $K^0$- and $\phi$ - mesons produced in the $pp$ collisions at $\sqrt{s}=2.76$ $TeV$ have been analyzed by fitting them using the exponential function. It was observed that the distributions contain several $p_T$ regions similar to the cases with the charged particles, $\pi^0$- and $\eta$- mesons produced in the same events. These regions could be characterized...
This work discusses a phenomenological quark-diquark nucleon model based on light-front soft-wall AdS/QCD holography able to be used in particle collision simulations.
The light-front holography has predicted two particle bound state wave function inside nucleons which can not be derived simply from a picture of valence quarks, namely diquarks [1]. In this framework, from the construction of...
Centrality is an important concept in a 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 at midrapidity or spectator fragments emitted in the forward rapidity region. Relation between collision geometry and...
A possibility to obtain the spectrum of mesons (as quark-antiquark states) in effective model of Quantum Chromodynamics on the Light Front (LF) is considered. We use the effective Hamiltonian on the LF having the quark fields interracting with the zero modes of gluon fields. This effective Hamiltonian includes these terms in such a way that one can get quark-antiquark bound states. We chose...
Density distributions of many nuclei in their ground states are not spherically symmetric and are described by modified Woods–Saxon distributions using spherical harmonics [1]. Collisions of deformed $^{129}$Xe, $^{197}$Au and $^{238}$U nuclei were studied, in particular, in the ALICE experiment at the LHC [2] and in the STAR experiment at RHIC [3]. I was shown [4], that collision events with...
In our work we systematized various holographic models and relations between them. We started by constructing the most general theory that has a quadratic in fields, holographic 5D action violating the Poincaré invariance along the fifth coordinate, but which still produces linear Regge mass spectrum. This setup shows that a solvable Soft-Wall (SW) model with linear spectrum can have two...
Nucleons which escape interactions with nucleons of the collision partner in collisions of relativistic nuclei move forward and form spectator matter. Reliable models describing the properties of spectator matter are of particular interest for modeling the response of forward calorimeters in experiments at NICA [1,2] and at the LHC [3]. In ultracentral collisions of nuclei a fireball with a...
Role of photon-exchange in proton-nucleus collisions with forward large rapidity gaps at LHC energies is discussed.
Relative contributions via gamma- and pomeron- exchanges for forward large rapidity gap events in proton-lead collisions are estimated.
The obtained results compared with recent preliminary CMS data at LHC.
We study the equation of state of quark gluon plasma (QGP) with dynamic strong and intense magnetic field. This magnetic field is expected to be generate due to the collisions of massive nuclei at relativistic heavy ion collider and large hadron collider. To get a deeper understanding of QGP physical picture, we use a quasi-particle model with various initial condition. The calculation results...
The yields of charmed particles are the important observables sensitive to critical phenomena in QCD-matter at high baryon density. Highly efficient registration of such short-lived products of nuclear interactions using the Inner Tracking System (ITS) of Multi-Purpose Detector (MPD) based on Monolithic Active Pixel Sensors will play a key role in the charm production analysis.
The...
Since the results the from European Muon Collaboration (EMC)
indicated that the combined quarks and anti-quarks account for only
about one-quarter of the proton spin, theories and experiments have
been trying to understand and measure the contributions from other
sources. Gluons have been of particular interest in the last couple of
decades. Spin asymmetry measurements from proton-proton...
Recent years have shown how important a role in resonance spectroscopy is played by theoretical limits imposed on amplitudes. They are unitarity and crossing symmetry. Generally, it is about the analysis of the analytical structure of complex amplitudes, which are so important that, for example, they eliminate long-existing ambiguities in experimental data and dramatically change the resonance...
Ultra-peripheral heavy-ion collisions provide a unique opportunity to study two-photon induced processes. The production of tau lepton pairs in the process $\mathrm{Pb}+\mathrm{Pb} \rightarrow \mathrm{Pb}+\mathrm{Pb} + \tau^{+}\tau^{-}$ at the LHC is particularly interesting since its cross section is sensitive to poorly known electromagnetic moments of the $\tau$-lepton. Possible deviations...
Recently, much attention has been paid to the effects of interaction of quantised fields with macro-objects. This area of research is important for the development of both theoretical and experimental physics, and there is every reason to believe that their results will find many scientific and technical applications. Here, to construct the models necessary for theoretical research, the...
In a few months, the accelerator complex of the Booster and Nuclotron at JINR (Dubna) will be ready to accelerate heavy ions. At the same time, the Baryonic Matter at Nuclotron (BM@N) experimental setup is completing its configuration to investigate relativistic heavy-ion beam interactions with fixed targets.
One of the most important experimental tasks of the BM@N physics program is...
The theory of superalgebraic spinors [1] - [6] is an extension of the theory of algebraic spinors [7]. It is a modern version of algebraic quantum field theory. The main difference of this theory from other versions of quantum field theory is that the field operators in it are the superposition of Grassmann densities in momentum space and their derivatives. In this case, gamma operators...
The upgrade program of the Multi-Purpose Detector (MPD) experiment at the Nuclotron-Based Ion Collider Facility (NICA) complex considers assembly and installation of an Inner Tracking System (ITS) made of Monolitic Active Pixel Sensors (MAPSs) between the beam pipe and the Time Projection Chamber (TPC). It is expected that the new detector will enhance the experimental potential for...
The future MPD experiment at the NICA collider is aimed to study hot and dense matter created in heavy ion collisions at center-of-mass energies from 4 to 11 GeV. Measurements of photon spectra via reconstruction of electron-positron pairs from photon conversions provide a unique opportunity to probe the temperature of the produced medium and study $\pi^0$ and eta meson yields down to low...
The Higgs boson within the Standard Model (SM) has been discovered by the ATLAS and CMS experiments in 2012. However analyzing a larger volume of LHC dataset collected by the CMS detector from 2016 to 2018 at a higher center of mass energy ($\sqrt{s}$ = 13 TeV) is expected to shed more light on the Higgs boson properties and would improve the related measurement sensitivity. Few comprehensive...
Fluctuations of relative yield of neutral and charged pions are expected to be sensitive to the creation of quark-gluon matter, pion Bose-condensate or chiral phase transition, which may take place in AA, pA or even pp collisions. Quantitatively, such fluctuations can be estimated using the variable $\nu_{dyn}$ which, by its construction, reduces or completely removed most of the collisional...
With the full LHC Run 2 pp collision dataset collected at 13 TeV, very detailed measurements of Higgs boson properties can be performed using its decays into bosons. This talk presents measurements of Higgs boson properties using decays into bosons and their combination with fermionic decays, including production mode cross sections and simplified template cross sections, as well as their...
Femtoscopy is a tool to measure the spatial and temporal characteristics of a system produced after a collision of two nuclei happened. Currently, it is not possible to directly measure these properties of the system, however, femtoscopy rely on a different approach to accomplish this task, it uses momentum correlations of particle pairs. Those correlations originate from quantum statistics...
The femtoscopic studies done by the ALICE Collaboration provided results with unprecedented precision for the short-range strong interactions between different hadron pairs. The next challenge is the development of the three-particle femtoscopy which will deliver the first ever direct measurement of genuine three-body forces. Such results would be a crucial input for the low-energy QCD and...
Testing the Yukawa couplings of the Higgs boson to quarks and leptons is important to understand the origin of fermion masses. The talk presents several new measurements in Higgs boson decays to two bottom quarks or two tau leptons, searches for Higgs boson decays to two charm quarks or two muons, as well as indirect constraints of the charm-Yukawa coupling. The production of Higgs bosons in...
Measurements of fluctuations allow one to study phase transitions and other collective phenomena in systems formed in high-energy hadronic collisions.
In this report, we will discuss properties of a recently proposed fluctuation observable, namely, the correlation coefficient between ratios of identified particle yields measured in two angular acceptance windows. With such an observable it is...
As the heaviest known fundamental particle, the top quark has taken a central role in the study of fundamental interactions. Production of top quarks in pairs provides an important probe of strong interactions. The top quark mass is a key fundamental parameter which places a valuable constraint on the Higgs boson mass and electroweak symmetry breaking. Observations of the relative rates and...
Difficulties associated with the multiplicity of particle production in proton collisions at the LHC and with theoretical description of hadronization lead to assumptions about a new physics in studying the angles of escape and energy of jets. Problems of such physics are connected with the vacuum properties related to the hierarchy problem. The explanation of difficulties of Standard Model...
In the search for the critical point of strongly interacting matter one of the key methods is the study of the event-by-event fluctuations of different event observables. One important aspect of this research is an accurate definition of the initial conditions event-wise. Namely, the influence of the trivial fluctuations, such as those of the system volume should be eliminated in the studied...
Combining measurements of many production and decay channels of the observed Higgs boson allows for the highest possible measurement precision for the properties of the Higgs boson and its interactions. These combined measurements are interpreted in various ways; specific scenarios of physics beyond the Standard Model are tested, as well as a generic extension in the framework of the Standard...
The using of strongly intensive observables are considered as a way to suppress the contribution of trivial ”volume” fluctuations in experimental studies of the correlation and fluctuation phenomena [1]. In this regard, we study the properties of the strongly intensive variable $Σ$ characterizing correlations between the number of particles produced in two observation windows separated by a...
The possible correlation between the yield of strange and heavy-flavour particles and the emission of particles in the region outside pN-kinematics (the so-called cumulative region) in pA collisions is studied. The particle production in the cumulative area is considered as a trigger, confirming participation in the process of a dense few-nucleon cluster. From the modern point of view this...
Several theories beyond the Standard Model predict the existence of new particles decaying into pairs of gauge bosons. These states generally have masses larger than that of the Higgs boson, while some theories predict resonances with masses smaller than it. The latest ATLAS results on searches for such resonances in final states with leptons and photons based on pp collision data collected at...
Studies of multiplicity fluctuations and the shape of multiplicity distributions (e.g. the KNO scaling) are among the basic components of relativistic nuclear physics. Combinants being the linear combinations of ratios of probabilities, as well as widely used cumulants, are quantities that characterize a distribution. Recently it was found that combinants obtained from multiplicity...
The search for new physics such as supersymmetry (SUSY) and other beyond-the-standard-model physics is a major goal of the LHC physics program. The talk will cover the most recent results of SUSY and Exotica searches using 137 fb$^{-1}$ data collected in 2016-2018 with the CMS detector at the LHC.
The measurement of the flux of low-energy cosmic antinuclei may reveal the existence of exotic processes such as dark matter annihilation, since the production rate of these ions through ordinary collisions between cosmic rays and the interstellar matter is very low. However, the lack of experimental data at low energies, where both the antinuclei production and inelastic cross sections are...
Z-peak tag-n-probe method was widely used for estimation of electron-to-photon misidentification rate for photon-oriented studies in Run I and in early Run II pp-collisions data. The increased luminosity and energy of collisions in Run II requires an improvement of the existing method, especially it is necessary for a description of underlying background spectra in the Z boson mass region of...
The production of a pair of Z-bosons in the llυυ channel (l = e, μ) is studied with the conditions of proton-proton collisions at a centre-of-mass energy of 13 TeV. The generation of signal and background events is performed using the MadGraph5_aMC@NLO Monte Carlo event generator. The Pythia8 and Delphes3 frameworks are used for event showering, hadronization, and detector response...
The Large Hadron Collider (LHC) has completed in 2018 its second working phase and the experiments have collected data sets of proton–proton collisions at center-of-mass energies of 13 TeV with an integrated luminosity of about 140 $\mathrm{fb}^{−1}$ . This report reviews the status of standard model measurements with the CMS experiment at the LHC.
Heavy-flavour quarks (charm and beauty) are excellent probes for the study of the properties of the quark-gluon plasma (QGP), a colour-deconfined medium produced in ultra-relativistic heavy-ion collisions. Being produced on shorter time scales than the typical QGP formation time and having negligible thermal production and in-medium annihilation rates, heavy quarks experience the full QGP...
Recent results of the ATLAS experiment on charmonium production in proton-proton at 8 and 13 TeV collisions will be presented. The measurement of the associated production of the J/psi meson and a gauge boson, including the separation of single and double parton scattering components, will be discussed. The measurement of J/psi and psi(2S) differential cross sections will be reported as...
The quark-gluon plasma (QGP) is a strongly-interacting deconfined state of matter produced in ultra-relativistic heavy-ion collisions. In order to study the QCD matter and its evolution, quarkonia, bound states of a heavy quark and antiquark pair, are preferred tools as they are sensitive to the first stages of the collision and to the evolution of the created system. The study of the...
This talk gives an overview of the latest ultra-peripheral physics measurements performed with the ATLAS detector at the LHC. These include differential measurements of the exclusive di-muon production cross-section, which are crucial for setting constraints on the initial photon spectrum for all UPC measurements at the LHC; measurements of light-by-light scattering, which result in an...
The short-lived hadronic resonances are used to study the properties of the hot and dense medium produced in relativistic heavy-ion collisions. Due to their short lifetimes, the resonance yields and peak shapes measured in the hadronic channels are sensitive to rescattering and regeneration effects in the hadronic phase. Besides, the resonances with different strangeness content and baryonic...
The studies of nuclear reactions involving deuterons play an important role in the understanding of the structure of the nucleons and the dynamics of nuclear interactions. The study of processes involving the deuteron helps to solve many actual relativistic problems of nuclear physics, such as nucleon-nucleon interaction at high energies, the structure of light nuclei at small inter-nucleon...
$\bf{A.T. D’yachenko^{1,2}, I.A. Mitropolsky^{2}}$
$^{1}$Emperor Alexander I Petersburg State Transport University, St. Petersburg, Russia
$^{2}$B.P. Konstantinov Petersburg Nuclear Physics Institute, NRC “Kurchatov Institute”, Gatchina, Russia
The main purpose of the study of heavy ion collisions is to study the equation of state of nuclear matter (EOS - equation of state). Along...
The electromagnetic probes are one of the unique probe which determine the state of quark gluon plasma (QGP). These are only the signal which travel through the whole space-time volume due to weak interaction from surrounding medium. With theoretical quasiparticle model, we found that production rate increases with increase the chemical potential values. By including the chemical potential,...
A new approach to deal with the scattering amplitudes in Glauber theory
is proposed. It relies on the use of generating function, that has been explicitly
found. The main advantage of the method is in a relatively simple analytical form
that allows to carry out calculations
in the all interaction orders of the Glauber theory.
Until now the only way to do it
without additional...
Phase structure of quark matter with chiral and isospin imbalance is considered in the framework of effective models. There has been considered as two color as well as three color QCD. It was shown that chiral imbalance has several rather peculiar properties such as being universal catalyzer, i. e. it catalyzes all the considered symmetry breaking patterns in the system, including the diquark...
Fragments charge has been measured with the forward hodoscope (FWall) in the HADES experiment for Ag+Ag@1.58AGeV and Au+Au@1.23AGeV. First results on the nuclei fragments description with the framework of the DCM-QGSM-SMM model and comparison with the experimental data will be presented. The description of the fragments within the model is a crucial task to determine the collision centrality...
A further development of Monte Carlo model of pp, pA and AA collisions with string fusion [1-3] is made for a more detailed description of the multiple hadron production both in small and large transverse momentum areas.
An effective dipole partonic cascade was implemented, taking into account the Lorenz invariance of the observed values. Thus, a single parameter will remain in the model...
A broad class of theoretical scenarios called “the Higgs-portal models” describes the interaction of dark matter with the “usual” matter only through the Higgs sector. From an experimental point of view, the models provide an interesting intersection of several directions in the search for new physics, namely, the study of non-standard properties of the observed Higgs boson, the search for new...
The first experiment at the upgraded BM@N on the study of particle production in Xe+CsI at 4.0 AGeV collisions is planned at the beginning of 2022. To measure the centrality of nucleus collisions in this reaction the new forward hadron calorimeter FHCal will be used. The performance of new upgraded forward hadron calorimeter with transverse and longitudinal segmentations is shown. Results...
