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arXiv · 2503.18103

In-medium nucleon-nucleon cross sections from relativistic ab initio calculations

Tianyu Wang·Hui Tong·Chencan Wang·Xiaoying Qu·Sibo Wang
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Abstract

The in-medium nucleon-nucleon scattering cross section is a pivotal quantity for studying the medium effects of strong interaction, and its precise knowledge is critical for understanding the equation of state for dense matter, intermediate-energy heavy-ion collision dynamics, and related phenomena. In this work, we perform a microscopic investigation of in-medium nucleon-nucleon scattering cross sections, by utilizing the relativistic Brueckner-Hartree-Fock (RBHF) theory with the Bonn potential. The fully incorporation of both positive- and negative-energy states in the RBHF solutions allows us to determine the single-particle potentials, the effective G matrix, and the scattering cross section uniquely. The momentum, density, and isospin dependence of the cross section for pp, nn, and np scattering are studied in detail. Our results provide a solid foundation for future parametrization studies of multiparameter dependency of total scattering cross sections.

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Tianyu Wang, Hui Tong, Chencan Wang, Xiaoying Qu, Sibo Wang. 2025-03-23. In-medium nucleon-nucleon cross sections from relativistic ab initio calculations. https://doi.org/10.1103/2cn8-s9ss

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