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The European Physical Journal C

, Volume 61, Issue 4, pp 779–784 | Cite as

Medium dependence of multiplicity distributions in MLLA

  • Néstor Armesto
  • Carlos Pajares
  • Paloma Quiroga-Arias
Regular Article - Theoretical Physics

Abstract

We study the modification of the multiplicity distributions in MLLA due to the presence of a QCD medium. The medium is introduced through a multiplicative constant (f med) in the soft infrared parts of the kernels of the QCD evolution equations. Using the asymptotic ansatz for mean multiplicities of the quark and gluons, 〈n G〉=e γ y and 〈n Q〉=r −1e γ y , respectively, we study two cases: fixed γ as previously considered in the literature, and fixed α s . We find opposite behaviors of the dispersion of the multiplicity distributions with increasing f med in both cases. For fixed γ the dispersion decreases, while for fixed α s it increases.

Keywords

Multiplicity Distribution Star Collaboration Factorial Moment Splitting Kernel Resummation Scheme 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag / Società Italiana di Fisica 2008

Authors and Affiliations

  • Néstor Armesto
    • 1
  • Carlos Pajares
    • 1
  • Paloma Quiroga-Arias
    • 1
  1. 1.Departamento de Física de Partículas and IGFAEUniversidade de Santiago de CompostelaSantiago de CompostelaSpain

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