A measurement of the gluon splitting rate into c(c)over-bar pairs in hadronic Z decays

Abstract

The rate of gluon splitting into c ̄c pairs in hadronic Z decays is measured using the data sample collected by ALEPH from 1991 to 1995. The selection is based on the identification of leptons (electrons and muons) originating from semileptonic charm decays, and on the topological properties of signal events. The result derived from the selected sample is gc ̄c = (3.26 ± 0.23(stat) ± 0.42(syst))%.