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Information × Registration Number 0219U100938, 0114U005072 , R & D reports Title Causal equation of state of hadron matter and its kinetic freeze-out criterion in the relativistic heavy ion collisions popup.stage_title Head Bugaev Kyrylo O., Доктор фізико-математичних наук Registration Date 05-04-2019 Organization Bogolybov Institute for Theoretical Physics of NASU popup.description2 We formulated a statistical equation of state for the multicomponent mixtures with the Van der Waals repulsion which has a phase transition from the gas to a compressible liquid. Its exact analytical solution is found. Within the multicomponent hadron resonance gas model, a high quality fit of experimental hadronic multiplicities was achieved for the center-of-mass collision energies √s of heavy ions from 2.2 GеV/nucl. to 200 GеV/nucl. with chi^2/dof=1,15. It is found that at low values of √s the deviation of strange particles from chemical equilibrium is an enhancement. On the basis of developed equation of state the problem of selective suppression of lambda-hyperons is resolved for the first time. Also for the first time we obtained a high quality description of the multiplicity ratio of lambda-hyperons to pi-mesons. Using the suggested hadron resonance gas model, we studied thermodynamics of hadronic mixtures at chemical freeze-out. For the collision energies √s = 4.9 GеV/nucl. and √s = 9.2 GеV/nucl. we found the novel irregularities among which there are two peaks of the dimensionless interaction measure and kinks in the √s-dependence of Λ-hyperon yield per proton and positive kaon’s yield per lambda-hyperon. We formulated a hypothesis that these collision energies correspond to two mixed quark-gluon-hadron phases. On the basis of two-component Carnahan-Starling equation of state a new version of the hadron resonance gas model is formulated; its speed of sound of hadronic systems is analyzed, and it is shown that, compared to traditional approach, the causality region is essentially expanded.  Product Description popup.authors Ivanytskyi Oleksii I. Ivanchuk Tetyana V. Bugaev Kyrylo O. Oliinychenko Dmytro R. Sagun Violetta V. popup.nrat_date 2020-04-02 Close