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arXiv · 1309.1573

Charm mass effects in bulk channel correlations

Y. Burnier·M. Laine
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Abstract

The bulk viscosity of thermalized QCD matter at temperatures above a few hundred MeV could be significantly influenced by charm quarks because their contribution arises four perturbative orders before purely gluonic effects. In an attempt to clarify the challenges of a lattice study, we determine the relevant imaginary-time correlator (of massive scalar densities) up to NLO in perturbation theory, and compare with existing data. We find discrepancies much larger than in the vector channel; this may hint, apart from the importance of taking a continuum limit, to larger non-perturbative effects in the scalar channel. We also recall how a transport peak related to the scalar density spectral function encodes non-perturbative information concerning the charm quark chemical equilibration rate close to equilibrium.

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Y. Burnier, M. Laine. 2013-11-13. Charm mass effects in bulk channel correlations. https://doi.org/10.1007/jhep11(2013)012

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