Fluctuations and the rapidity dependence of charged particles spectra in fixed centrality bins in pA collisions

We argue that large fluctuations in the saturation momentum are necessary to explain the ATLAS and ALICE data on p A collisions measured at the LHC. Using a form for the distribution of fluctuations motivated by theoretical studies of the non-linear evolution equations for the Color Glass Condensate, we find a remarkably good agreement between theory and the measured distributions. If the saturation momentum fluctuates, we argue that the cross section for a proton probe should also fluctuate, consistent with previous observations