Parton branching in the low x regime and multiplicity distributions at the LHC

Abstract

We study the multiplicity distribution measured in pp collisions at the LHC using a distribution which is derived from the Giovannini equations under the assumption that the evolution parameter is energy dependent. We obtain a negative binomial distribution with explicit energy dependence and fit it to three data sets, corresponding to different pseudorapidity and transverse momentum cuts, and also verify the applicability of the model for a fourth data set, corresponding to jets. We find a reasonable agreement with data for all sets.