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Title: Multiplicity Difference between Heavy and Light Quark Jets Revisited

Abstract

A peculiar prediction of perturbative QCD, obtained within the Local Parton Hadron Duality (LPHD) framework, is that the multiplicity difference {delta}Ql between heavy and light quark jets produced in e+e- annihilation is energy independent. In the Modified Leading Logarithmic Approximation (MLLA) the corresponding constant is derived in terms of a few experimentally measurable quantities. While the energy independence of {delta}Ql has been successfully verified experimentally for b-quarks up to the highest LEP2 energy, its numerical prediction ({delta}{sub bl}{sup MLLA} = 5.5 {+-} 0.8) overestimates the experimental results. The work presented in this talk, done in collaboration with Yuri L. Dokshitzer, Valery A. Khoze and Wolfgang Ochs, shows that in the light of new experimental results and the improvement in the understanding of the experimental data, this prediction needs indeed a revision. We now find {delta}bl = 4.4 {+-} 0.4, in better agreement with experiment, and we shaw that the remaining difference can be attributed largely to next-to-MLLA contributions, an important subset of which are identified and evaluated. The situation with charmed quarks is also reviewed.

Authors:
 [1]
  1. INFN e Dipartimento di Fisica dell' Universita, viale Berti Pichat 6/2, 40127 Bologna (Italy)
Publication Date:
OSTI Identifier:
20800115
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 828; Journal Issue: 1; Conference: 35. internationals symposium on multiparticle dynamics; Workshop on particle correlations and femtoscopy, Kromeriz (Czech Republic), 9-17 Aug 2005; Other Information: DOI: 10.1063/1.2197393; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANNIHILATION; APPROXIMATIONS; B QUARKS; C QUARKS; D QUARKS; DUALITY; ELECTRON-ELECTRON INTERACTIONS; GLUONS; HADRONS; JET MODEL; MULTIPLICITY; QUANTUM CHROMODYNAMICS; U QUARKS

Citation Formats

Fabbri, Fabrizio. Multiplicity Difference between Heavy and Light Quark Jets Revisited. United States: N. p., 2006. Web. doi:10.1063/1.2197393.
Fabbri, Fabrizio. Multiplicity Difference between Heavy and Light Quark Jets Revisited. United States. doi:10.1063/1.2197393.
Fabbri, Fabrizio. Tue . "Multiplicity Difference between Heavy and Light Quark Jets Revisited". United States. doi:10.1063/1.2197393.
@article{osti_20800115,
title = {Multiplicity Difference between Heavy and Light Quark Jets Revisited},
author = {Fabbri, Fabrizio},
abstractNote = {A peculiar prediction of perturbative QCD, obtained within the Local Parton Hadron Duality (LPHD) framework, is that the multiplicity difference {delta}Ql between heavy and light quark jets produced in e+e- annihilation is energy independent. In the Modified Leading Logarithmic Approximation (MLLA) the corresponding constant is derived in terms of a few experimentally measurable quantities. While the energy independence of {delta}Ql has been successfully verified experimentally for b-quarks up to the highest LEP2 energy, its numerical prediction ({delta}{sub bl}{sup MLLA} = 5.5 {+-} 0.8) overestimates the experimental results. The work presented in this talk, done in collaboration with Yuri L. Dokshitzer, Valery A. Khoze and Wolfgang Ochs, shows that in the light of new experimental results and the improvement in the understanding of the experimental data, this prediction needs indeed a revision. We now find {delta}bl = 4.4 {+-} 0.4, in better agreement with experiment, and we shaw that the remaining difference can be attributed largely to next-to-MLLA contributions, an important subset of which are identified and evaluated. The situation with charmed quarks is also reviewed.},
doi = {10.1063/1.2197393},
journal = {AIP Conference Proceedings},
number = 1,
volume = 828,
place = {United States},
year = {Tue Apr 11 00:00:00 EDT 2006},
month = {Tue Apr 11 00:00:00 EDT 2006}
}