Exclusive dilepton production in ultraperipheral lead-lead collisions in the ATLAS experiment

Exclusive dilepton pairs are produced via electromagnetic interactions in ultrapripheral heavy-ion collisions (UPC). Electromagnetic fields associated to relativistic lead nuclei can be considered as fluxes of quasi-real photons. The dilepton photoproduction, $\gamma\gamma\rightarrow\ell^{+}\ell^{-}$, is one of the fundamental processes in UPC and therefore can provide a reference for other processes. Given the large theoretical uncertainty of photon flux modelling, its precise measurement with exclusive dilepton pairs can improve predictions for other photoproduction processes. The results for the $\gamma\gamma\rightarrow\mu^{+}\mu^{-}$ process using 2015 Pb+Pb data collected by the ATLAS experiment at the Large Hadron Collider are presented along with control distributions for the $\gamma\gamma\rightarrow e^{+}e^{-}$ process in 2018 Pb+Pb data.