Finite-energy correction to the branching equation for multiplicity distributions

Multiplicity distributions for the nonjet component in hadronic collisions can be described by the negative-binomial solution of the branching equation. The latter can be regarded as the infinite-energy limit of a dynamical model of clusters, which produces particles by cluster branching. At finite energy, energy-momentum conservation can no longer be ignored during cluster branching, and the usual branching equation must be modified. This paper deals with the derivation of the modified branching equation and its solution. It turns out that the finite-energy modification to the distribution is unexpectedly small owing to an intricate structure of the branching chains