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Title Helicity and vorticity in heavy-ion collisions at energies available at the JINR Nuclotron-based Ion Collider facility Author info N. S. Tsegelnik, E. E. Kolomeitsev, V. Voronyuk Author Tsegelnik Nikita S. (33%)
Co-authors Kolomeitsev Evgeni E. 1970- (34%) UMBFP06 - Katedra fyziky
Voronyuk Vadym (33%)
Source document Physical Review C. Vol. 107, no. 3 (2023), pp. 1-21. - Maryland : American Physical Society, 2023 Keywords ťažké ióny elektrónové urýchľovače helicita - helicity Form. Descr. články - journal articles Language English Country United States of America URL Link na plný text Public work category ADC No. of Archival Copy 54071 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title Lambda and anti-Lambda Freeze-Out Distributions and Global Polarizations in Au+Au Collisions Par.title Λ and (Λ)over-bar Freeze-Out Distributions and Global Polarizations in Au plus Au Collisions Author info Nikita Tsegelnik, Evgeni Kolomeitsev, Vadym Voronyuk Author Tsegelnik Nikita S. (34%)
Co-authors Kolomeitsev Evgeni E. 1970- (33%) UMBFP06 - Katedra fyziky
Voronyuk Vadym (33%)
Source document Particles. Vol. 6, no. 1 (2023), pp. 373-384. - Basel : Multidisciplinary Digital Publishing Institute, 2023 Language English Country Switzerland URL Link na plný text Public work category ADM No. of Archival Copy 54073 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title Hybrid model with viscous relativistic hydrodynamics: a role of constraints on the shear-stress tensor Author info A. S. Khvorostukhin ... [et al.] Author Khvorostukhin A. S. (34%)
Co-authors Kolomeitsev Evgeni E. 1970- (33%) UMBFP06 - Katedra fyziky
Toneev V. D. (33%)
Source document The European Physical Journal A : Hadrons and Nuclei. Vol. 57, no. 10 (2021), pp. 294-1-294-25. - New York : Springer Nature, 2021 Keywords relativistic hydrodynamics heavy ion collisions viscosity Form. Descr. články - journal articles Language English Country Germany Annotation We present the hybrid model connecting the parton–hadron–string dynamic model (PHSD) and a hydrodynamic model taking into account shear viscosity within the Israel–Stewart approach. The numerical scheme, initialization, and particlization procedure are discussed in detail. The performance of the code is tested on the pion and proton rapidity and transverse mass distributions calculated for Au + Au and Pb+Pb collisions at AGS–SPS energies. The influence of the switch time from transport to hydro models, the viscous parameter, and freeze-out time are discussed. Since the applicability of the Israel–Stewart hydrodynamics assumes the perturbative character of the viscous stress tensor, πμν, which should not exceed the ideal energy–momentum tensor, T μν id , hydrodynamical codes usually rescale the shear stress tensor if the inequality πμν T μν id is not fulfilled in some sense. There are several conditions used in the literature and we analyze in detail the influence of different conditions and values of the cut-off parameter on observables.We show that the form of the corresponding condition plays an important role in the sensitivity of hydrodynamic calculations to the viscous parameter – a ratio of the shear viscosity to the entropy density, η/s. It is shown that the constraints used in the vHLLE and MUSIC models give the same results for the observables.With these constraints, the rapidity distributions and transverse momentum spectra are most sensitive to a change of the η/s ratio. We demonstrate that these constraints do not guarantee that each element of the πμν tensor is smaller than the corresponding element T μν id . As an alternative, a strict condition is used. When applied it reduces the sensitivity of the proton and pion momentum distributions to the viscosity parameter. We performed global fits of the rapidity and transverse mass distributions of pion and protons. It was also found that η/s as a function of the collision energy monotonically increases from Elab = 6 AGeV up to Elab = 40 AGeV and saturates for higher SPS energies. We observe that it is difficult to reproduce simultaneously pion and proton rapidity distribution within our model with the present choice of the equation of state without a phase transition. URL Link na plný text Public work category ADC No. of Archival Copy 50708 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title Charge and isospin fluctuations in a non-ideal pion gas with dynamically fixed particle number Author info Evgeni E. Kolomeitsev ... [et al.] Author Kolomeitsev Evgeni E. 1970- (34%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (33%)
Borisov Maxim E. (33%)
Source document The European Physical Journal A : Hadrons and Nuclei. Vol. 57, no. 4 (2021), pp. [1-29]. - Berlin : Springer, 2021 Keywords Bose-Einsteinova kondenzácia - Bose-Einstein condensation heavy ion collisions Form. Descr. články - journal articles Language English Country Germany Public work category ADC No. of Archival Copy 49947 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title On cooling of neutron stars with a stiff equation of state including hyperons Author info Hovik Grigorian, Evgeni E. Kolomeitsev ... [et al.] Author Grigorian Hovik (25%)
Co-authors Kolomeitsev Evgeni E. 1970- (25%) UMBFP06 - Katedra fyziky
Maslov Konstantin A. (25%)
Voskresensky Dmitri (25%)
Source document Universe. Vol. 4, no. 2 (2018), pp. 1-6. - Basel : Multidisciplinary Digital Publishing Institute, 2018 Keywords equation of state neutron stars neutrína - neutrinos Language English Country Switzerland systematics 53 Annotation Exploiting a stiff equation of state of the relativistic mean-field model MKVORHf with sigma-scaled hadron effective masses and couplings, including hyperons, we demonstrate that the existing neutron-star cooling data can be appropriately described within “the nuclear medium cooling scenario” under the assumption that different sources have different masses URL Link na zdrojový dokument Public work category ADM No. of Archival Copy 43911 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title Charged rho meson condensate in neutron stars within RMF models Author info Konstantin A. Maslov, Evgeni E. Kolomeitsev, Dmitry N. Voskresensky Author Maslov Konstantin A. (34%)
Co-authors Kolomeitsev Evgeni E. 1970- (33%) UMBFP06 - Katedra fyziky
Voskresensky Dmitri (33%)
Source document Universe. Vol. 4, no. 1 (2018), pp. 1-8. - Basel : Multidisciplinary Digital Publishing Institute, 2018 ; Compact stars in the QCD Phase Diagram medzinárodná konferencia Keywords neutron stars equation of state rho meson condensation maximum mass Delta resonances Language English Country Switzerland systematics 53 Annotation Knowledge of the equation of state (EoS) of cold and dense baryonic matter is essential for the description of properties of neutron stars (NSs). With an increase of the density, new baryon species can appear in NS matter, as well as various meson condensates. In previous works, we developed relativistic mean-field (RMF) models with hyperons and Δ -isobars, which passed the majority of known experimental constraints, including the existence of a 2 M ⊙ neutron star. In this contribution, we present results of the inclusion of ρ − -meson condensation into these models. We have shown that, in one class of the models (so-called KVOR-based models, in which the additional stiffening procedure is introduced in the isoscalar sector), the condensation gives only a small contribution to the EoS. In another class of the models (MKVOR-based models with additional stiffening in isovector sector), the condensation can lead to a first-order phase transition and a substantial decrease of the NS mass. Nevertheless, in all resulting models, the condensation does not spoil the description of the experimental constraints URL https://www.mdpi.com/2218-1997/4/1/1 Public work category AFC No. of Archival Copy 43907 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title Fluctuations in non-ideal pion gas with dynamically fixed particle number Author info E. E. Kolomeitsev, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (50%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (50%)
Source document Nuclear Physics A. Vol. 973, (2018), pp. 89-103. - Amsterdam : Elsevier B.V., 2018 Keywords heavy ion collisions fluctuations Hartree approximation Bose-Einsteinova kondenzácia - Bose-Einstein condensation Language English Country Netherlands systematics 53 Annotation We consider a non-ideal hot pion gas with the dynamically fixed number of particles in the model with the λφ4interaction. The effective Lagrangian for the description of such a system is obtained after dropping the terms responsible for the change of the total particle number. Reactions π+π−↔π0π0, which deter-mine the isospin balance of the medium, are permitted. Within the self-consistent Hartree approximation we compute the effective pion mass, thermodynamic characteristics of the system and the variance of the particle number at temperatures above the critical point of the induced Bose–Einstein condensation when the pion chemical potential reaches the value of the effective pion mass. We analyze conditions for the con-densate formation in the process of thermalization of an initially non-equilibrium pion gas. The normalized variance of the particle number increases with a temperature decrease but remains finite in the critical point of the Bose–Einstein condensation. This is due to the non-perturbative account of the interaction and is in contrast to the ideal-gas case. In the kinetic regime of the condensate formation the variance is shown to stay finite also URL Link na plný text Public work category ADC No. of Archival Copy 43902 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title Charged rho-meson condensation in neutron stars Author info Evgeni E. Kolomeitsev, K. A. Maslov ... [et al.] Author Kolomeitsev Evgeni E. 1970- (34%) UMBFP06 - Katedra fyziky
Co-authors Maslov K. A. (33%)
Voskresensky Dmitri (33%)
Source document Nuclear Physics A. Vol. 970, (2018), pp. 291-315. - Amsterdam : Elsevier B.V., 2018 Keywords neutron stars equation of state condensation Language English Country Netherlands systematics 53 Annotation We extend relativistic mean-field models with hadron masses and meson–baryon coupling constants dependent on the scalar field σ, including hyperons and (1232)baryons, to incorporate a possibility of the charged ρmeson condensation in neutron star matter. The influence of the ρ−condensation on the equation of state proves to be strongly model dependent. In our models of one type (KVORcut-based ones) the ρ−condensation arises by a second-order phase transition above a critical density and the maximum value of the neutron star mass diminishes only slightly. The matter composition changes more significantly. In our models of other type (MKVOR*-based ones), if the system is considered at fixed density, the ρ−condensation arises by a second-order phase transition at the baryon density n =n(II)c,ρand at a slightly higher density n =n(I)c,ρthere occurs a first-order phase transition. In a neutron star matter starting with a density n <n(II)c,ρthere appears a region of a mixed phase, or the system is described by Maxwell construction, that results in a substantial decrease of the value of the maximum neutron star mass. Nevertheless in the models under consideration the observational constraint on the maximum neutron star mass is fulfilled. Besides, in MKVOR*-based models the appearance of the ρ−condensate is accompanied by a strong rearrangement of the matter composition. Dependence of the results on a choice of the ρmeson scaling functions for the effective ρmeson mass and coupling constants is also investigated URL Link na plný text Public work category ADC No. of Archival Copy 43905 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika Title Particle number fluctuations in a non-ideal pion gas Author info Evgeni E. Kolomeitsev, Maxim E. Borisov, Dmitry N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (98%) UMBFP06 - Katedra fyziky
Co-authors Borisov Maxim E. (1%)
Voskresensky Dmitri (1%)
Source document 6th international conference on new frontiers in physics (ICNFP 2017). Pp. [1-7]. - Les Ulis : Édition Diffusion Presse Sciences, 2018 ; International conference on new frontiers in physics (ICNFP 2017) medzinárodná konferencia Note Príspevok je evidovaný v databáze Scopus. Keywords particle number fluctuations pion gas particle physics Language English Country France systematics 53 Annotation We consider a non-ideal hot pion gas with the dynamically fixed number of particles in the model with the lambda-phi^4 interaction. The effective Lagrangian for the description of such a system is obtained by dropping the terms responsible for the change of the total particle number. Within the self-consistent Hartree approximation, we compute the effective pion mass, thermodynamic characteristics of the system and identify a critical point of the induced Bose-Einstein condensation when the pion chemical potential reaches the value of the effective pion mass. The normalized variance, skewness, and kurtosis of the particle number distributions are calculated. We demonstrate that all these characteristics remain finite at the critical point of the Bose-Einstein condensation. This is due to the non-perturbative account of the interaction and is in contrast to the ideal-gas case URL Link na zdrojový dokument Public work category AFC No. of Archival Copy 43933 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ Title Vorticity and hyperon polarization at energies available at JINR Nuclotron-based Ion Collider fAcility Author info E. E. Kolomeitsev, V. D. Toneev ... [et al.] Author Kolomeitsev Evgeni E. 1970- (34%) UMBFP06 - Katedra fyziky
Co-authors Toneev V. D. (33%)
Voronyuk Vadym (33%)
Source document Physical Review C. Vol. 97, no. 6 (2018), pp. [1-9]. - Maryland : American Physical Society, 2018 Keywords heavy ion collisions vorticity hyperon polarization Language English Country United States of America systematics 53 Annotation We study the formation of fluid vorticity and the hyperon polarization in heavy-ion collisions at energies available at the JINR Nuclotron-based Ion Collider fAcility in the framework of the parton-hadron-string dynamic model, taking into account both hadronic and quark-gluonic (partonic) degrees of freedom. The vorticity properties in peripheral Au+Au collisions at √sNN= 7.7 GeV are demonstrated and confronted with other models. The obtained result for the Lambda polarization is in agreement with the experimental data by the STAR Collaboration, whereas the model is not able to explain the observed high values of the antihyperon anti-Lambda polarization URL Link na plný text Public work category ADC No. of Archival Copy 43912 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika