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arXiv · 0808.1288

Fragmentation Function in Non-Equilibrium QCD Using Closed-Time Path Integral Formalism

Gouranga C Nayak
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Abstract

In this paper we implement Schwinger-Keldysh closed-time path integral formalism in non-equilibrium QCD to the definition of Collins-Soper fragmentation function. We consider a high p_T parton in QCD medium at initial time t_0 with arbitrary non-equilibrium (non-isotropic) distribution function f(\vec{p}) fragmenting to hadron. We formulate parton to hadron fragmentation function in non-equilibrium QCD in the light-cone quantization formalism. It may be possible to include final state interactions with the medium via modification of the Wilson lines in this definition of the non-equilibrium fragmentation function. This may be relevant to study hadron production from quark-gluon plasma at RHIC and LHC.

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Gouranga C Nayak. 2009-01-09. Fragmentation Function in Non-Equilibrium QCD Using Closed-Time Path Integral Formalism. https://doi.org/10.1140/epjc%2Fs10052-008-0854-5

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