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arXiv · 2306.02829

Dynamic Calculations of Magnetic Field and Implications on Spin Polarization and Spin Alignment in Heavy Ion Collisions

Hui Li·Xiao-Liang Xia·Xu-Guang Huang·Huan Zhong Huang
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Abstract

Magnetic field plays a crucial role in various novel phenomena in heavy-ion collisions. We solve the Maxwell equations numerically in a medium with time-dependent electric conductivity by using the Finite-Difference Time-Domain (FDTD) algorithm. We investigate the time evolution of magnetic fields in two scenarios with different electric conductivities at collision energies ranging from $\sqrt{s_\text{NN}}=$ 7.7 to 200 GeV. Our results suggest that the magnetic field may not persist long enough to induce a significant splitting between the global spin polarizations of $\Lambda$ and $\bar{\Lambda}$ at freeze-out stage. However, our results do not rule out the possibility of the magnetic field influencing the spin (anti-)alignment of vector mesons.

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Hui Li, Xiao-Liang Xia, Xu-Guang Huang, Huan Zhong Huang. 2023-06-05. Dynamic Calculations of Magnetic Field and Implications on Spin Polarization and Spin Alignment in Heavy Ion Collisions. https://arxiv.org/abs/2306.02829

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