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arXiv · 2502.03185

Anisotropic excited bottomonia from a basis of smeared operators

Ryan Bignell·Gert Aarts·Chris Allton·M. Naeem Anwar·Timothy J. Burns·Rachel Horohan D'arcy·Benjamin Jäger·Seyong Kim·Maria Paola Lombardo·Sinéad Ryan·Jon-Ivar Skullerud·Antonio Smecca
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Abstract

Bottomonia play a crucial role in our understanding of the quark gluon plasma. We present lattice non-relativistic QCD calculations of bottomonia at temperatures in the range $T \in [47, 380]$ MeV using the Fastsum Generation 2L anisotropic $N_f = 2 + 1$ ensembles. The use of a basis of smeared operators allows the extraction of excited-state masses at zero temperature and an investigation of their thermal properties at non-zero temperature. We find that the ground state signal is substantially improved by this variational approach at finite temperature. We also apply the time-derivative moments approach to the projected or optimal correlation functions at finite temperature.

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Ryan Bignell, Gert Aarts, Chris Allton, M. Naeem Anwar, Timothy J. Burns, Rachel Horohan D'arcy, Benjamin Jäger, Seyong Kim, Maria Paola Lombardo, Sinéad Ryan, Jon-Ivar Skullerud, Antonio Smecca. 2025-02-05. Anisotropic excited bottomonia from a basis of smeared operators. https://arxiv.org/abs/2502.03185

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