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arXiv · 0809.4428

Medium dependence of multiplicity distributions in MLLA

N. Armesto·C. Pajares·P. Quiroga-Arias
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Abstract

We study the modification of the multiplicity distributions in MLLA due to the presence of a QCD medium. The medium is introduced though a multiplicative constant ($f_{med}$) in the soft infrared parts of the kernels of QCD evolution equations. Using the asymptotic ansatz for quark and gluons mean multiplicities $ =e^{γy}$ and $ =r^{-1}e^{γy}$ 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.

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N. Armesto, C. Pajares, P. Quiroga-Arias. 2008-09-25. Medium dependence of multiplicity distributions in MLLA. https://doi.org/10.1140/epjc%2Fs10052-008-0829-6

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