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arXiv · 1903.03025

Low-momentum pion enhancement from schematic hadronization of a gluon-saturated initial state

Elizaveta Nazarova·Łukasz Juchnowski·David Blaschke·Tobias Fischer
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Abstract

We study the particle production in the early stage of the ultrarelativistic heavy-ion collisions. To this end the Boltzmann kinetic equations for gluons and pions with elastic rescattering are considered together with a simple model for the parton-hadron conversion process (hadronisation). It is shown that the overpopulation of the gluon phase space in the initial state leads to an intermediate stage of Bose enhancement in the low-momentum gluon sector which due to the gluon-pion conversion process is then reflected in the final distribution function of pions. This pattern is very similar to the experimental finding of a low-momentum pion enhancement in the ALICE experiment at CERN LHC. Relations to the thermal statistical model of hadron production and the phenomenon of thermal and chemical freeze-out are discussed in this context.

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Elizaveta Nazarova, Łukasz Juchnowski, David Blaschke, Tobias Fischer. 2019-03-07. Low-momentum pion enhancement from schematic hadronization of a gluon-saturated initial state. https://doi.org/10.3390/particles2010010

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