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arXiv · 1402.6210

The bottomonium spectrum at finite temperature from $N_f=2+1$ lattice QCD

Abstract

We present results on the bottomonium spectrum at temperatures above and below the deconfinement crossover temperature, $T_c$, from dynamical lattice QCD simulations. The heavy quark is treated with a non-relativistic effective field theory on the lattice and serves as a probe of the hot medium. Ensembles with a finer spatial lattice spacing and a greater range of temperatures below $T_c$ than those previously employed by this collaboration are used. In addition, there are $N_f=2+1$ flavours of Wilson clover quark in the sea with $M_π\approx400$ MeV and we perform a more careful tuning of the bottom quark mass in this work. We calculate the spectral functions of S and P wave bottomonium states using the maximum entropy method and confirm earlier findings on the survival of the ground state S wave states up to at least $2T_c$ and the immediate dissociation of the P wave states above $T_c$.

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Gert Aarts, Chris Allton, Tim Harris, Seyong Kim, Maria Paola Lombardo, Sinéad M. Ryan, Jon-Ivar Skullerud. 2014-02-25. The bottomonium spectrum at finite temperature from $N_f=2+1$ lattice QCD. https://doi.org/10.1007/jhep07(2014)097

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