Investigating subnucleonic structures via new measurements of incoherent J/

Ultra-peripheral collisions of heavy ions provide a unique environment to study the gluon structure of nuclei through photon-induced reactions. In particular, the incoherent photoproduction of J/ψ vector meson is sensitive to event-by-event fluctuations of the gluon field at nucleon and subnucleonic scales. We report new ALICE measurement of incoherent J/ψ production in Pb–Pb collisions at √sNN = 5.02 TeV, differential in both photon-nucleus energy and Mandelstam-|t|. At low |t|, the cross section rises with increasing photon-nucleus energy, while at larger |t| the growth is suppressed with respect to the trend at low |t|. This measurement represents the first study of incoherent photoproduction at the LHC performed as a function of both WγPb,n and |t|.