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arXiv · 2204.02761

Lepton pair photoproduction in peripheral relativistic heavy-ion collisions

Abstract

We study the lepton pair photoproduction in peripheral heavy-ion collisions based on the formalism in our previous work [Phys. Rev. D 104, 056011 (2021)]. We present the numerical results for the distributions of the transverse momentum, azimuthal angle and invariant mass for $e^{+}e^{-}$ and $\mu^{+}\mu^{-}$ pairs as functions of the impact parameter and other kinematic variables in Au+Au collisions. Our calculation incorporates the information on the transverse momentum and polarization of photons which is essential to describe the experimental data. We observe a broadening effect in the transverse momentum for lepton pairs with and without smear effects. We also observe a significant enhancement in the distribution of $\cos(2\varphi)$ for $\mu^{+}\mu^{-}$ pairs. Our results provide a baseline for future studies of other higher order corrections beyond Born approximation and medium effects in the lepton pair production.

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Ren-jie Wang, Shuo Lin, Shi Pu, Yi-fei Zhang, Qun Wang. 2022-04-06. Lepton pair photoproduction in peripheral relativistic heavy-ion collisions. https://doi.org/10.1103/physrevd.106.034025

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