2025/07/01 by Zihan Liu, Ziyang Li, Liu, Zihan +5
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Theory (hep-th) #High-Energy Particle Collisions Research #Nuclear Experiment (nucl-ex) #Nuclear Theory (nucl-th) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2507.00706
openalex publication_date 2025/07/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
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 ρ00, the spin alignment parameter, for K*0, ϕ, and ρ0 mesons in Au+Au collisions at √(sNN) = 7.7 - 200 GeV. Our results reveal that the measurable ρ00 - 1/3 remains unaffected for ϕ, while shows significantly negative (positive) deviations for K*0 and ρ0 with respect to the reaction (production) plane. Quantitatively, the maximum deviation reaches -0.0056 (0.0268) for K*0 and -0.0122 (0.0414) for ρ0 with respect to the reaction (production) plane. Notably, the deviations in ρ00 for both K*0 and ρ0 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.