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arXiv · 2503.17315

Spectral properties of bottomonium at high temperature: a systematic investigation

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

We investigate spectral features of bottomonium at high temperature, in particular the thermal mass shift and width of ground state S-wave and P-wave state. We employ and compare a range of methods for determining these features from lattice NRQCD correlators, including direct correlator analyses (multi-exponential fits and moments of spectral functions), linear methods (Backus-Gilbert, Tikhonov and HLT methods), and Bayesian methods for spectral function reconstruction (MEM and BR). We comment on the reliability and limitations of the various methods.

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Jon-Ivar Skullerud, Gert Aarts, Chris Allton, M. Naeem Anwar, Ryan Bignell, Timothy J. Burns, Rachel Horohan D'arcy, Benjamin Jäger, Seyong Kim, Maria Paola Lombardo, Ben Page, Sinéad M. Ryan, Antonio Smecca, Tom Spriggs. 2025-03-21. Spectral properties of bottomonium at high temperature: a systematic investigation. https://arxiv.org/abs/2503.17315

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