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arXiv · hep-ph/0509364

Multiplicity distributions for jet parton showers in a medium

Abstract

The "jet-quenching" interpretation of suppressed high-pT hadron production at RHIC implies that jet multiplicity distributions and jet-like particle correlations in heavy-ion collisions at RHIC and LHC differ strongly from those seen at e+e- or pp colliders. Here, we present an approach for describing the changes induced by the medium, which implements jet quenching as a probabilistic medium-modified parton shower, treating leading and subleading parton splittings on an equal footing. We show that the strong suppression of single inclusive hadron spectra measured in Au-Au collisions at RHIC implies a characteristic distortion of the single inclusive distribution of soft partons inside the jet. We determine, as a function of jet energy, to what extent the soft jet fragments can be measured above some momentum cut.

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Nicolas Borghini, Urs Achim Wiedemann. 2005-09-30. Multiplicity distributions for jet parton showers in a medium. https://doi.org/10.1016/j.nuclphysa.2006.06.084

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