Energy dependence of rescattering effect on vector mesons spin alignment at RHIC
Abstract
Spin alignment of vector mesons in heavy-ion collisions provides a novel probe of quark polarization and hadronization mechanism in quark-gluon plasma. Hadronic rescattering may affect the measured spin alignment of vector mesons due to non-uniform rescattering probability in non-central heavy-ion collisions. Using the UrQMD model, we systematically investigated the hadronic rescattering effect on the measurement of , the spin alignment parameter, for , , and mesons in Au+Au collisions at = 7.7 - 200 GeV. Our results reveal that the measurable remains unaffected for , while shows significantly negative (positive) deviations for and with respect to the reaction (production) plane. Quantitatively, the maximum deviation reaches () for and () for with respect to the reaction (production) plane. Notably, the deviations in for both and increase monotonically with increasing collision energy. These findings underscore the critical necessity of accounting for rescattering effects when interpreting spin alignment measurements of short-lived vector mesons in heavy-ion collisions.
Cite
@article{arxiv.2507.00706,
title = {Energy dependence of rescattering effect on vector mesons spin alignment at RHIC},
author = {Zihan Liu and Ziyang Li and Wangmei Zha and Zebo Tang},
journal= {arXiv preprint arXiv:2507.00706},
year = {2025}
}
Comments
9 pages, 8 figures