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arXiv · 1710.08858

Continuum extrapolation of quarkonium correlators at non-zero temperature

Heng-Tong Ding·Olaf Kaczmarek·Anna-Lena Kruse·Hiroshi Ohno·Hauke Sandmeyer
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Abstract

In the investigation of in-medium modifications of quarkonia and for determining heavy quark diffusion coefficients, correlation functions play a crucial role. For the first time we perform a continuum extrapolation of charmonium and bottomonium correlators in the vector channel based on non-perturbatively clover-improved Wilson fermions in quenched lattice QCD. Calculations were done at 4 different lattice spacings, spatial extents between 96 and 192, aspect ratio from 1/6 to 1/2, for 5 temperatures between $T/T_c = 0.75$ and $T/T_c = 2.2$. We interpolate between different quark masses to match to the same vector meson mass over different lattice setups. Afterwards we extrapolate the renormalized correlators to the continuum. While we find a strong temperature dependence for charmonium, bottomonium states are only slightly affected at higher temperatures.

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Heng-Tong Ding, Olaf Kaczmarek, Anna-Lena Kruse, Hiroshi Ohno, Hauke Sandmeyer. 2017-10-24. Continuum extrapolation of quarkonium correlators at non-zero temperature. https://doi.org/10.1051/epjconf%2F201817507010

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