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arXiv · 2506.22247

Spin polarization from nucleon-nucleon scatterings in intermediate-energy heavy-ion collisions

Rong-Jun Liu·Jun Xu·Yu-Gang Ma
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Abstract

We propose a new mechanism of generating spin polarization in heavy-ion collisions dominated by nucleon degree of freedom. By incorporating the spin change in nucleon-nucleon scatterings based on the phase shift data together with the constraint of rigorous angular momentum conservation and Pauli blocking, we illustrate through a Boltzmann-Uehling-Uhlenbeck transport model that appreciable spin polarization (about $1 \sim 2\%$) can be generated in intermediate-energy heavy-ion collisions. This mechanism, together with the nuclear spin-orbit potential, may help to understand the spin polarization in few-GeV heavy-ion collisions dominated by nucleon degree of freedom.

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Rong-Jun Liu, Jun Xu, Yu-Gang Ma. 2025-06-27. Spin polarization from nucleon-nucleon scatterings in intermediate-energy heavy-ion collisions. https://doi.org/10.1016/j.physletb.2025.139703

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