Mapping color fluctuations in the photon in ultraperipheral heavy ion collisions at the Large Hadron Collider

Abstract

We model effects of color fluctuations (CFs) in the light-cone photon wave function and for the first time make predictions for the distribution over the number of wounded nucleons $\nu$ in the inelastic photon-nucleus scattering. We show that CFs lead to a dramatic enhancement of this distribution at $\nu=1$ and large $\nu > 10$. We also study the implications of different scales and CFs in the photon wave function on the total transverse energy $\Sigma E_T$ and other observables in inelastic $\gamma A$ scattering with different triggers. Our predictions can be tested in proton-nucleus and nucleus-nucleus ultraperipheral collisions at the LHC and will help to map CFs, whose first indications have already been observed at the LHC.