DFTT 56/96 MPI-PhT/96-90 LU TP 96-25 COMMON ORIGIN OF THE SHOULDER STRUCTURE AND OF THE OSCILLATIONS OF MOMENTS IN MULTIPLICITY DISTRIBUTIONS IN ee ANNIHILATIONS

We show, via a simple parametrization of the multiplicity distribution of charged particles in ee annihilation at the Z peak in terms of the weighted superposition of two negative binomial distributions, that both the shoulder structure in the intermediate multiplicity range and the oscillation in sign of the ratio of factorial cumulants over factorial moments of increasing order are related to hard gluon radiation. Talk presented at the 7th International Workshop “Correlations and Fluctuation” (Nijmegen, The Netherlands, June 30 – July 6, 1996) and at the 28th International Conference on High Energy Physics – ICHEP 96 (Warsaw, Poland, July 25–31, 1996). E-mail: [email protected] E-mail: [email protected] E-mail: [email protected] COMMON ORIGIN OF THE SHOULDER STRUCTURE AND OF THE OSCILLATIONS OF MOMENTS IN MULTIPLICITY DISTRIBUTIONS IN ee ANNIHILATIONS