Speaker
Description
The strong electromagnetic field generated by the colliding nuclei in heavy-ion collisions can be represented by a spectrum of equivalent photons, leading to photon-induced interactions. Significant enhancements of the J/$\psi$ production via $e^{+}e^{-}$ decay channel at very low transverse momentum ($p_{T}$) have been observed by the STAR and ALICE collaborations in peripheral heavy-ion collisions. The excess yields exhibit a much weaker centrality dependence compared to the expectation for hadronic production, and are consistent with coherent photon-nucleus interactions. Measurement of J/$\psi$ production via $\mu^{+}\mu^{-}$ decay channel can provide additional inputs to investigate these phenomena.
In 2014 and 2016, the STAR experiment recorded large samples of Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$ = 200 GeV with the di-muon trigger enabled by the Muon Telescope Detector. In this presentation, we will show the measurement of invariant yield and nuclear modification factor of $J/\psi$ at $p_{T} <$ 0.15 GeV/c via $\mu^{+}\mu^{-}$ decay channel. Physics implications will also be discussed.
