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arXiv · 1311.3208

Bottomonium spectrum at finite temperature

Tim Harris·Sinéad M. Ryan·Gert Aarts·Chris Allton·Seyong Kim·Maria Paola Lombardo·Jon-Ivar Skullerud
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Abstract

We investigate the modification of S and P wave states in the bottomonium spectrum above and below the deconfinement crossover temperature through their spectral functions obtained from the maximum entropy method. Anisotropic ensembles with $N_f=2+1$ Wilson clover fermions with tadpole-improvement are used while the bottom quark is treated with an improved non-relativistic action. We observe significant modifications of the P wave $χ_{b1}$ ground state directly above the crossover temperature, $T_c$, while the S wave $Υ$ ground state remains relatively unchanged up to temperatures of almost $2T_c$. This evidence supports earlier conclusions from our FASTSUM collaboration of the immediate dissociation of the P wave states above $T_c$ and the survival of the S wave ground states up to $2T_c$.

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Tim Harris, Sinéad M. Ryan, Gert Aarts, Chris Allton, Seyong Kim, Maria Paola Lombardo, Jon-Ivar Skullerud. 2013-11-15. Bottomonium spectrum at finite temperature. https://arxiv.org/abs/1311.3208

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