Photoproduction of $J/ψ$ in d+Au ultraperipheral collisions at the BNL Relativistic Heavy Ion Collider

Abstract

In this letter, we argue that the STAR data on J/ψ photoproduction in d + Au UPCs is not sensitive to leading twist gluon nuclear shadowing, gluon saturation, or details of the deuteron wave function, but instead primarily probes elastic and possibly proton-dissociative J/ψ photoproduction on quasi-free nucleons. Analyzing the STAR detector capabilities for selection of UPC events, we explore the possibility that the contribution of proton-dissociative J/ψ photoproduction is negligibly small and obtain a very good description of the t dependence of the STAR total cross section.