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Isospin Dependence of Nucleon-Nucleon Elastic Cross Section

Qingfeng Li·Zhuxia Li·Guangjun Mao
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Abstract

The in-medium neutron-proton, proton-proton(neutron-neutron) scattering cross sections($σ_{np}^{*}$, $σ_{pp(nn)}^{*}$) are studied based on QHD-II type Lagrangian within the framework of the microscopic transport theory. The results demonstrate that, for free nucleon-nucleon scattering cross sections, the isospin dependence is dominantly caused by $ρ$ meson field. The medium correction of nucleon-nucleon scattering cross sections is also isospin dependent, $σ_{np}^{*}$ depends on the baryon density weakly and $σ_{pp(nn)}^{*}$ depends on the baryon density significantly, which is due to the different effects of the medium correction of nucleon mass and $ρ$ meson mass on $σ_{np}$ and $σ_{pp(nn)}$, respectively

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Qingfeng Li, Zhuxia Li, Guangjun Mao. 2000-05-06. Isospin Dependence of Nucleon-Nucleon Elastic Cross Section. https://doi.org/10.1103/physrevc.62.014606

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