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Energy scan/dependence of kinetic freeze-out scenarios of multi-strange and other identified particles in central nucleus-nucleus collisions

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 نشر من قبل Fu-Hu Liu
 تاريخ النشر 2020
  مجال البحث
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The transverse momentum (mass) spectra of the multi-strange and non-multi-strange (i.e. other identified) particles in central gold-gold (Au-Au), lead-lead (Pb-Pb), argon-muriate (Ar-KCl) and nickel-nickel (Ni-Ni) collisions over a wide energy range have been studied in this work. The experimental data measured by various collaborations have been analyzed. The blast-wave fit with Tsallis statistics is used to extract the kinetic freeze-out temperature and transverse flow velocity from the experimental data of transverse momentum (mass) spectra. The extracted parameters increase with the increase of collision energy and appear with the trend of saturation at the Beam Energy Scan (BES) energies at the Relativistic Heavy Ion Collider (RHIC). This saturation implies that the onset energy of phase transition of partial deconfinement is 7.7 GeV and that of whole deconfinement is 39 GeV. Furthermore, the energy scan/dependence of kinetic freeze-out scenarios are observed for the multi-strange and other identified particles, though the multiple freeze-out scenarios are also observed for various particles.

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