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arXiv · 2112.04201

A comparison of spectral reconstruction methods applied to non-zero temperature NRQCD meson correlation functions

Thomas Spriggs·Gert Aarts·Chris Allton·Timothy Burns·Rachel Horohan D'Arcy·Benjamin Jäger·Seyong Kim·Maria-Paola Lombardo·Sam Offler·Ben Page·Sinead M. Ryan·Jon-Ivar Skullerud
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Abstract

We present results from the fastsum collaboration's programme to determine the spectrum of the bottomonium system as a function of temperature. Three different methods of extracting spectral information are discussed: a Maximum Likelihood approach using a Gaussian spectral function for the ground state, the Backus Gilbert method, and the Kernel Ridge Regression machine learning procedure. We employ the fastsum anisotropic lattices with 2+1 dynamical quark flavours, with temperatures ranging from 47 to 375 MeV.

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Thomas Spriggs, Gert Aarts, Chris Allton, Timothy Burns, Rachel Horohan D'Arcy, Benjamin Jäger, Seyong Kim, Maria-Paola Lombardo, Sam Offler, Ben Page, Sinead M. Ryan, Jon-Ivar Skullerud. 2021-12-08. A comparison of spectral reconstruction methods applied to non-zero temperature NRQCD meson correlation functions. https://doi.org/10.1051/epjconf/202225805011

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