The 14th Workshop on QCD Phase Transition and Relativistic Heavy-Ion Physics (QPT 2021)

The production of $\Omega NN$ and $\Omega\Omega N$ in heavy ion collisions

Not scheduled

15m

Conference Hall (Shangshan Hotel, Building 9)

Speaker

良 张 (Shanghai Institute of Applied Physics, Chinese Academy of Sciences)

Description

Even though lots of $\Lambda$-hypernuclei have been found and measured, hypernuclei consisting of multi-strangeness, such as $\Omega$-hypernuclei, are not yet discovered. The studies of multi-strangeness hypernuclei help us further understand the interaction between hyperons and nucleons. Recently the HAL-QCD Collaboration calculated $\Omega N$ and $\Omega\Omega$ interactions by lattice Quantum Chromo Dynamics (LQCD) simulations and predicted $\Omega$-dibaryon with binding energy about 1\textasciitilde2 MeV. According to the results, yields of $\Omega$-dibaryons in Au + Au collisions at RHIC and Pb + Pb collisions at LHC energies were estimated by a coalescence model. And this work discusses the production of $\Omega NN$ and $\Omega\Omega N$ as well as their decay channels. %A variational method was used in calculations of bound states and binding energy of $\Omega NN$ and $\Omega\Omega N$ with the potentials form the HAL-QCD's results. The three-body bound state problem can be solved through a variation method coupled with an eigenvalue problem. And for weakly-bounded thrid particle, the folding model is applied. %The $N$-$\Omega$ and $\Omega$-$\Omega$ potential used in this work fitted from the lattice QCD's simulation near the physical point which is reported by HAL QCD colaboration. The production of $\Omega NN$ and $\Omega\Omega N$ were estimated by using a Blast-wave model plus coalescence model for heavy ion collisions at $\sqrt{s_{NN}} = 200$ GeV and $2.76$ TeV. In coalescence model, the phase-space infomation of nucleons and $\Omega$ are generated by Blast-wave model and the particles are coalesced into $\Omega NN$ and $\Omega\Omega N$ by using the Wigner density function from the simplified three-body wave function. The predicted production of $\Omega$-hypernuclei are %$N\Omega$ $\sim\times 10^{-4}$, $\Omega\Omega$ $\sim\times 10^{-7}$, $\Omega NN$ $\sim\times 10^{-6}$ and $N\Omega\Omega$ $\sim\times 10^{-9}$. And the productions of $\Omega$-hypernuclei in Pb+Pb collisions at 2.76 TeV is larger than that in Au+Au collisions at 200 GeV.With the growing of constituents number $A$ the hypernuclei $\Omega \rightarrow p\Omega \rightarrow pn\Omega$, the production appears to follow the exponential function $\exp(-bA)$. This $A$ dependence tend is similar to that for light nuclei of $p \rightarrow d \rightarrow t$. And the decay modes of $\Omega NN$ and $\Omega\Omega N$ are simply discussed in order to find the $\Omega NN$ and $\Omega\Omega N$ in future experiments, which will provide a method to understand the $YN$ and $YY$ interactions for higher strangeness. And the systematic measurement of hypernuclei can shed light on the production mechanism and the baryon interactions.