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arXiv · 2303.10474

Bayesian inference of in-medium baryon-baryon scattering cross sections from HADES proton flow data

Bao-An Li·Wen-Jie Xie
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Abstract

Within a Bayesian statistical framework using a Gaussian Process emulator for an isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model simulator of heavy-ion reactions at intermediate energies, we infer from the HADES proton flow data the posterior probability distribution functions of in-medium baryon-baryon scattering cross section modification factor X with respect to free-space and the corresponding incompressibility K of nuclear matter as well as their correlation function. The mean value of X is found to be $X=1.32^{+0.28}_{-0.40}$ at 68\% confidence level assuming the nuclear incompressibility K will not exceed 400 MeV, providing circumstantial evidence for enhanced baryon-baryon scattering cross sections in hot and dense nuclear matter.

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Bao-An Li, Wen-Jie Xie. 2023-07-24. Bayesian inference of in-medium baryon-baryon scattering cross sections from HADES proton flow data. https://doi.org/10.1016/j.nuclphysa.2023.122726

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