Langevin dynamics and decoherence of heavy quarks at high temperatures

Yukinao Akamatsu

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arXiv · 1503.08110

Langevin dynamics and decoherence of heavy quarks at high temperatures

Yukinao Akamatsu

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Abstract

A Langevin equation of heavy quarks in high-temperature quark-gluon plasma is derived. The dynamics of heavy quark color is coupled with the phase space dynamics and causes a macroscopic superposition state of heavy quark momentum. Decoherence of the superposition state allows one to use a classical description. The time scale of decoherence gives an appropriate discretization time scale $\Delta t\sim \sqrt{M/C_{\rm F}\gamma}$ for the classical Langevin equation, where $M$ is heavy quark mass and $\gamma$ is heavy quark momentum diffusion constant.

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Yukinao Akamatsu. 2015-03-27. Langevin dynamics and decoherence of heavy quarks at high temperatures. https://arxiv.org/abs/1503.08110

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