Decamp, D. and Finch, Alexander (1991) *Measurement of the charged particle multiplicity distribution in hadronic Z decays.* Physics Letters B, 273 (1-2). pp. 181-192. ISSN 0370-2693

## Abstract

The charged particle multiplicity distribution of hadronic Z decays was measured on the peak of the Z resonance using the ALEPH detector at LEP. Using a model independent unfolding procedure the distribution was found to have a mean 〈n〉=20.85±0.24 and a dispersion D=6.34±0.12. Comparison with lower energy data supports the KNO scaling hypothesis in the energy range GeV. At GeV the shape of the multiplicity distribution is well described by a log-normal distribution, as predicted from a cascading model for multi-particle production. The same model also successfully describes the energy dependence of the mean and width of the multiplicity distribution. A next-to-leading order QCD prediction in the framework of the modified leading-log approximation and local parton-hadron duality is found to fit the energy dependence of the mean but not the width of the charged multiplicity distribution, indicating that the width of the multiplicity distribution is a sensitive probe for higher order QCD or non-perturbative effects.

Item Type: | Journal Article |
---|---|

Journal or Publication Title: | Physics Letters B |

Subjects: | |

Departments: | Faculty of Science and Technology > Physics |

ID Code: | 63786 |

Deposited By: | ep_importer_pure |

Deposited On: | 07 May 2013 14:43 |

Refereed?: | Yes |

Published?: | Published |

Last Modified: | 11 Apr 2018 00:59 |

Identification Number: | |

URI: | http://eprints.lancs.ac.uk/id/eprint/63786 |

### Actions (login required)

View Item |