Charm counting in b decays

The inclusive production of charmed particles in Z--><b(b)over bar> decays has been measured from the yield of D-0, D+, D-s(+) and Lambda(c)(+) decays in a sample of <q(q)over bar> events with high b purity collected with the ALEPH detector from 1992 to 1995. From these measurements, adding the charmonia production rate and an estimate of the charmed strange baryon contribution, the average number of charm quarks per b decay is determined to be n(c)=1.230+/-0.036+/-0.038+/-0.053, where the uncertainties are due to statistics, systematic effects and branching ratios, respectively.