# IV international conference on particle physics and astrophysics

22-26 October 2018
Hotel Intourist Kolomenskoye 4*
Europe/Moscow timezone

## On separate chemical freeze-outs of hadrons and light (anti)nuclei in high energy nuclear collisions

23 Oct 2018, 10:50
10m
Alekseevskiy hall (Hotel Intourist Kolomenskoye 4*)

### Alekseevskiy hall

#### Hotel Intourist Kolomenskoye 4*

Kashyrskoye shosse, 39B, Moscow, Russia, 115409
Plenary/section talk Nuclear physics

### Speaker

Prof. Kyrill Bugaev (Bogolyubov Institute for Theoretical Phsycs)

### Description

The multiplicities of light (anti)nuclei were measured recently by the ALICE collaboration in Pb+Pb collisions at the center-of-mass collision energy $\sqrt{s} =2.76$ TeV [1]. Surprisingly, the hadron resonance gas model (HRGM) is able to perfectly describe the their multiplicities [2] under various assumptions. For instance, one can consider the (anti)nuclei with a vanishing hard-core radius (as the point-like particles) or with the hard-core radius of proton, but the fit quality is the same for these assumptions. However, it is clear that the hard-core radius of a nuclei consisting of A baryons or antibaryons must be give by the expression $R(A) = R(1) A^\frac{1}{3}$. To implement such a relation into the HRMG we employ the induced surface tension concept [3] and perform a thorough analysis of hadronic and (anti)nuclei multiplicities measured by the ALICE collaboration. The HRGM with the induced surface tension allows us to verify different assumptions on the values of hard-core radii and different scenarios of chemical freeze-out of (anti)nuclei. It is shown that the most successful description of hadrons can be achieved at the chemical freeze-out temperature $T_h=150$ MeV, while the one for all (anti)nuclei is $T_A=168$ MeV. Possible explanations of this very high temperature of (anti)nuclei chemical freeze-out are discussed.

1. J. Adam et al. [ALICE Collaboration], Phys. Rev. C 93, no. 2, 024917 (2016).

2. K. A. Bugaev, V. V. Sagun, A. I. Ivanytskyi, I. P. Yakimenko, E. G. Nikonov, A.V. Taranenko and G. M. Zinovjev, Nucl. Phys. A 970, 133 (2018).

3. V. V. Sagun, K. A. Bugaev, A. I. Ivanytskyi, I. P. Yakimenko, E. G. Nikonov, A.V. Taranenko, C. Greiner, D. B. Blaschke and G. M. Zinovjev, Eur. Phys. J. A 54, 100 (2018).

### Primary author

Prof. Kyrill Bugaev (Bogolyubov Institute for Theoretical Phsycs)

### Presentation Materials

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