Production of nuclei and hypernuclei in high-energy nuclear 
reactions. 

A.S. Botvina. 

INR , Russian Academy of Science, Moscow, Russia. 


We review the main mechanisms leading to the production of 
light and intermediate mass nuclei and hypernuclei in 
relativistic nuclei collisions. We demonstrate that in these 
many-body phenomena one can separate and describe the 
processes characterising excited nuclear matter properties 
which have a primary importance for nuclear/particle physics 
and astrophysics. Such deep-inelastic high-energy collisions 
do lead to the fragmentation (multifragmentation) of nuclear 
matter and, in addition, the hyper-fragments can be abundantly 
produced [1,2]. The binding energies of hyperons can be 
determined from the correlated hypernuclei yields [3,4], and 
this gives a chance to evaluate experimentally the hyperon 
effects in nuclear matter. The promising process for such a 
research is the disintegration of large excited nuclear and 
hyper-nuclear residues produced in peripheral nucleus-nucleus 
collisions. In central collisions, we prove a novel mechanism 
responsible for combining nucleons and hyperons into large 
clusters [5,6]: These cluster can be formed by the residual 
nuclear interaction at a low sub-nuclear density when the nuclear 
matter expands. One can describe this process within the 
statistical approach as a disintegration of the excited finite 
clusters of low (freeze-out) density. In the same time we have 
obtained the limitation on the temperature of such clusters 
which is important for all statistical nucleation processes 
in the expanding matter. Our approach is able to describe the 
FOPI experimental data measured in central collisions, in 
particular, nuclei yields, nuclei kinetic energies, and the 
modification of the nuclear isotope yields with increasing 
the beam energy. Previously, it was not possible with other 
models. This novel mechanism leads to the correlations of the 
produced nuclear species and to producing unstable hypernuclei 
states that can be used for the nuclei/hypernuclei identification. 
The transport and statistical models are used to describe 
the whole reaction. Concerning to hypernuclei studies we 
demonstrate the advantages of such reactions over the 
traditional hypernuclear methods: A broad distribution of 
predicted hypernuclei in masses and isospin allows for 
investigating properties of exotic hypernuclei. We point at 
the abundant production of multi-strange nuclei that will 
give an access to multi-hyperon systems and strange nuclear 
matter. The realistic estimates of nuclei and hypernuclei 
yields in various collisions are presented. 

[1] A.S. Botvina, et al., Phys. Rev. C95, 014902 (2017). 

[2] A.S. Botvina, et al., Phys. Rev. C94, 054615 (2016). 

[3] N. Buyukcizmeci, et al., Phys. Rev. C98, 064603 (2018). 

[4] N. Buyukcizmeci, et al., Eur. Phys. J. A56, 210 (2020). 

[5] A.S. Botvina, et al., Phys. Rev. C103, 064602 (2021). 

[6] A.S. Botvina, et al.,  arXiv:2203.17092 , (2022) , 
     accepted in Phys. Rev. C.