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arXiv · 2006.07365

Acoplanarity of QED pairs accompanied by nuclear dissociation in ultra-peripheral heavy ion collisions

James Daniel Brandenburg·Wei Li·Lijuan Ruan·Zebo Tang·Zhangbu Xu·Shuai Yang·Wangmei Zha
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Abstract

This paper investigates the transverse momentum broadening effect for electromagnetic production of dileptons in ultra-peripheral heavy ion collisions accompanied by nuclear dissociation. The electromagnetic dissociation probability of nuclei for different neutron multiplicities is estimated, which could serve as a centrality definition (i.e. impact parameter estimate) in ultra-peripheral collisions. In the framework of lowest-order QED, the acoplanarity of dilepton pairs is calculated for different neutron emission scenarios in ultra-peripheral collisions, indicating significant impact-parameter dependence. The verification of impact-parameter dependence is crucially important to understand the broadening effect observed in hadronic heavy-ion collisions.

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James Daniel Brandenburg, Wei Li, Lijuan Ruan, Zebo Tang, Zhangbu Xu, Shuai Yang, Wangmei Zha. 2020-06-12. Acoplanarity of QED pairs accompanied by nuclear dissociation in ultra-peripheral heavy ion collisions. https://arxiv.org/abs/2006.07365

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