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arXiv · 2206.02861

Heavy quark diffusion coefficient with gradient flow

Nora Brambilla·Viljami Leino·Julian Mayer-Steudte·Peter Petreczky
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Abstract

We calculate chromo-electric and chromo-magnetic correlators in quenched QCD at $1.5T_c$ and $10^4 T_c$ with the aim to estimate the heavy quark diffusion coefficient at leading order in the inverse heavy quark mass expansion, $\kappa_E$, as well as the coefficient of first mass suppressed correction, $\kappa_B$. We use gradient flow for noise reduction. At $1.5T_c$ we obtain: $1.70 \le \kappa_E/T^3 \le 3.12$ and $1.03< \kappa_B/T^3 < 2.61$. The latter implies that the mass suppressed effects in the heavy quark diffusion coefficient are 20% for bottom quarks and 34% for charm quark at this temperature.

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Nora Brambilla, Viljami Leino, Julian Mayer-Steudte, Peter Petreczky. 2022-06-06. Heavy quark diffusion coefficient with gradient flow. https://doi.org/10.1103/physrevd.107.054508

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