Jet multiplicity and soft gluon factorization

Abstract

On the basis of a factorization theorem for soft gluon insertions it is shown that leading log contributions to the multiplicity anomalous dimension come from ladder diagrams in a restricted region of phase space, in agreement with previous conjectures. This leads to a finite anomalous dimension ∼ α s and to a multiplicity behaviour ∼ exp ([ 2N c πb ] log[ Q 2 Λ 2 ]) 1 2 .