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arXiv · 1804.01813

Coherent lepton pair production in hadronic heavy ion collisions

W. Zha·L. Ruan·Z. Tang·Z. Xu·S. Yang
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Abstract

Recently, significant enhancements of $e^{+} e^{-}$ pair production at very low transverse momentum ($p_{T} < 0.15$ GeV/c) were observed by the STAR collaboration in peripheral hadronic A+A collisions. This excesses can not be described by the QGP thermal radiation and $ρ$ in-medium broadening calculations. This is a sign of coherent photon-photon interactions, which were conventionally studied only in ultra-peripheral collisions. In this article, we present calculations of lepton pair ($e^{+}e^{-}$ and $μ^{+}μ^{-}$) production from coherent photon-photon interactions in hadronic A+A collisions at RHIC and LHC energies within the STAR and ALICE acceptance.

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W. Zha, L. Ruan, Z. Tang, Z. Xu, S. Yang. 2018-04-05. Coherent lepton pair production in hadronic heavy ion collisions. https://doi.org/10.1016/j.physletb.2018.04.006

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