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Medium modifications of the nucleon-nucleon elastic cross section in neutron-rich intermediate energy HICs

Qingfeng Li·Zhuxia Li·Sven Soff·Marcus Bleicher·Horst Stoecker
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Abstract

Several observables of unbound nucleons which are to some extent sensitive to the medium modifications of nucleon-nucleon elastic cross sections in neutron-rich intermediate energy heavy ion collisions are investigated. The splitting effect of neutron and proton effective masses on cross sections is discussed. It is found that the transverse flow as a function of rapidity, the $Q_{zz}$ as a function of momentum, and the ratio of halfwidths of the transverse to that of longitudinal rapidity distribution $R_{t/l}$ are very sensitive to the medium modifications of the cross sections. The transverse momentum distribution of correlation functions of two-nucleons does not yield information on the in-medium cross section.

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Qingfeng Li, Zhuxia Li, Sven Soff, Marcus Bleicher, Horst Stoecker. 2006-01-17. Medium modifications of the nucleon-nucleon elastic cross section in neutron-rich intermediate energy HICs. https://doi.org/10.1088/0954-3899%2F32%2F4%2F001

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