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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 
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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 article
Title Temperatures and chemical potentials at kinetic freeze-out in relativistic heavy ion collisions from coarse grained transport simulations Author info Gabriele Inghirami, Paula Hillmann ... [et al.] Author Inghirami Gabriele (25%)
Co-authors Hillmann Paula (25%)
Tomášik Boris 1972- (25%) UMBFP06 - Katedra fyziky
Bleicher Marcus (25%)
Source document Journal of Physics G: Nuclear and Particle Physics. Vol. 47, no. 2 (2020), art. no. 025104, pp. [1-16]. - Bristol : IOP Publishing, 2020 Keywords ultrarelativistic heavy ion collisions freeze-out doprava - transportation - transport Form. Descr. články - journal articles Language English Country Great Britian Public work category ADC No. of Archival Copy 47346 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika 
unrecognised
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 unrecognised
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 unrecognised
Title Delta isobars in relativistic mean-field models with sigma-scaled hadron masses and couplings Author info E. E. Kolomeitsev, K. A. Maslov, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (98%) UMBFP06 - Katedra fyziky
Co-authors Maslov Konstantin A. (1%)
Voskresensky Dmitri (1%)
Source document Nuclear Physics A. Vol. 961 (2017), pp. 106-141. - Amsterdam : Elsevier B.V., 2017 Keywords neutron stars equation of state heavy ion collisions Language English Country Netherlands systematics 53 Annotation We extend the relativistic mean-field models with hadron masses and meson-baryon coupling constants dependent on the scalar sigma field, studied previously to incorporate Delta(1232) baryons. Available empirical information is analyzed to put constraints on the couplings of Delta s with meson fields. Conditions for the appearance of Delta s are studied. We demonstrate that with inclusion of the Delta s our equations of state continue to fulfill majority of known empirical constraints including the pressure-density constraint from heavy-ion collisions, the constraint on the maximum mass of the neutron stars, the direct Urea and the gravitational baryon mass ratio constraints. (C) 2017 Elsevier B.V. All rights reserved. Public work category ADC No. of Archival Copy 39909 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Directed flow in asymmetric nucleus-nucleus collisions and the inverse Landau-Pomeranchuk-Migdal effect Author info V. D. Toneev ... [et al.] Author Toneev V. D. (1%)
Co-authors Voronyuk Vadym (1%)
Kolomeitsev Evgeni E. 1970- (97%) UMBFP06 - Katedra fyziky
Cassing W. (1%)
Source document Physical Review C. Vol. 95, no. 3 (2017), pp. [1-6]. - Maryland : American Physical Society, 2017 Keywords heavy ion collisions energia - energy dense matter Language English Country United States of America systematics 53 Annotation It is proposed to identify a strong electric field-created during relativistic collisions of asymmetric nuclei-via the observation of pseudorapidity and transverse momentum distributions of hadrons with the same mass but opposite charge. The results of detailed calculations within the parton-hadron string dynamics (PHSD) approach for the charge-dependent directed flow v(1) are presented for semicentral Cu+Au collision at root S-NN = 200 GeV incorporating the inverse Landau-Pomeranchuk-Migdal (iLPM) effect, which accounts for a delay in the electromagnetic interaction with the charged degrees of freedom. By including the iLPM effect, we achieve a reasonable agreement of the PHSD results for the charge splitting in v(1)(p(T)) in line with the recent measurements by the STAR Collaboration for Cu+Au collisions at root s(NN) = 200 GeV while an instant appearance and coupling of electric charges at the hard collision vertex overestimates the splitting by about a factor of 10. We predict that the iLPM effect should practically disappear at energies of root s(NN) approximate to 9 GeV, which should lead to a significantly larger charge splitting of v1 at the future FAIR/NICA facilities. Public work category ADC No. of Archival Copy 39312 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Higher-order anisotropies in the blast-wave model: Disentangling flow and density field anisotropies Author info Jakub Cimerman ... [et al.] Author Cimerman Jakub 1994- (45%)
Co-authors Tomášik Boris 1972- (45%) UMBFP06 - Katedra fyziky
Csanád Máté (5%)
Lökös Sándor (5%)
Source document The European Physical Journal A : Hadrons and Nuclei. Vol. 53, no. 8 (2017), pp. [1-13]. - Berlin : Springer, 2017 Keywords ultrarelativistic heavy ion collisions femtoscopy anisotropic flow Language English Country United States of America systematics 53 Annotation We formulate a generalisation of the blast-wave model which is suitable for the description of higher-order azimuthal anisotropies of the hadron production. The model includes anisotropy in the density profile as well as an anisotropy in the transverse expansion velocity field. We then study how these two kinds of anisotropies influence the single-particle distributions and the correlation radii of two-particle correlation functions. Particularly we focus on the third-order anisotropy and consideration is given averaging over different orientations of the event plane. Public work category ADC No. of Archival Copy 41756 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Observables of non-equilibrium phase transition Author info Boris Tomášik ... [et al.] Author Tomášik Boris 1972- (45%) UMBFP06 - Katedra fyziky
Co-authors Schulc Martin (5%)
Melo Ivan (45%)
Kopečná Renata (5%)
Source document The European Physical Journal A : Hadrons and Nuclei. Vol. 52, no. 8 (2016), pp. 236-241. - Berlin : Springer, 2016 Keywords phase diagram strongly interacting matter heavy ion collisions Language English Country United States of America systematics 53 Public work category ADC No. of Archival Copy 37236 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Complete strangeness measurements in heavy-ion collisions Author info Boris Tomášik, Evgeni E. Kolomeitsev Author Tomášik Boris 1972- (50%) UMBFP06 - Katedra fyziky
Co-authors Kolomeitsev Evgeni E. 1970- (50%) UMBFP06 - Katedra fyziky
Source document The European Physical Journal A : Hadrons and Nuclei. Vol. 52, no. 8 (2016), pp. 251-256. - Berlin : Springer, 2016 Keywords heavy ion collisions strangeness Language English Country United States of America systematics 53 Public work category ADC No. of Archival Copy 37239 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised