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arXiv · 1706.01013

Simulating spin dynamics with spin-dependent cross sections in heavy-ion collisions

Yin Xia·Jun Xu·Bao-An Li·Wen-Qing Shen
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Abstract

We have incorporated the spin-dependent nucleon-nucleon cross sections into a Boltzmann-Uehling-Uhlenbeck transport model for the first time, using the spin-singlet and spin-triplet nucleon-nucleon elastic scattering cross sections extracted from the phase-shift analyses of nucleon-nucleon scatterings in free space. We found that the spin splitting of the collective flows is not affected by the spin-dependent cross sections, justifying it as a good probe of the in-medium nuclear spin-orbit interaction. With the in-medium nuclear spin-orbit mean-field potential that leads to local spin polarization, we found that the spin-averaged observables, such as elliptic flows of free nucleons and light clusters, becomes smaller with the spin-dependent differential nucleon-nucleon scattering cross sections.

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Yin Xia, Jun Xu, Bao-An Li, Wen-Qing Shen. 2017-10-11. Simulating spin dynamics with spin-dependent cross sections in heavy-ion collisions. https://doi.org/10.1103/physrevc.96.044618

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