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arXiv · 2502.03951

NRQCD Bottomonium at non-zero temperature using time-derivative moments

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

A well-known challenge for the lattice community is calculating the spectral function from the Euclidean correlator. We have approximated the spectral function and derived the mass and thermal width of particles through the time derivatives of the lattice correlator moments. We have focused on extracting the properties of bottomonium states, specifically $\Upsilon$ and $\chi_{b1}$. We will give an overview of the time-derivative moments approach and present results for the temperature dependence of the mass and width of both bottomonium states. The zero temperature results are consistent with experimental values, while results at higher temperatures are similar to those obtained using other methods.

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Rachel Horohan D'arcy, Gert Aarts, Chris Allton, Ryan Bignell, Timothy Burns, Benjamin Jaeger, Seyong Kim, Maria Paola Lombardo, Sinéad Ryan, Antonio Smecca, Jon-Ivar Skullerud. 2025-02-06. NRQCD Bottomonium at non-zero temperature using time-derivative moments. https://arxiv.org/abs/2502.03951

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