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arXiv · 2112.02075

Spectral reconstruction in NRQCD via the Backus-Gilbert method

Benjamin Page·Gert Aarts·Chris Allton·Benjamin Jäger·Seyong Kim·Maria Paola Lombardo·Sam Offler·Sinead M. Ryan·Jon-Ivar Skullerud·Thomas Spriggs
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Abstract

We present progress results from the FASTSUM collaboration's programme to determine the spectrum of the bottomonium system as a function of temperature using a variety of approaches. In this contribution, the Backus Gilbert method is used to reconstruct spectral functions from NRQCD meson correlator data from FASTSUM's anisotropic ensembles at nonzero temperature. We focus in particular on the resolving power of the method, providing a demonstration of how the underlying resolution functions can be probed by exploiting the Laplacian nature of the NRQCD kernel. We conclude with estimates of the bottomonium ground state mass and widths at nonzero temperature.

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Benjamin Page, Gert Aarts, Chris Allton, Benjamin Jäger, Seyong Kim, Maria Paola Lombardo, Sam Offler, Sinead M. Ryan, Jon-Ivar Skullerud, Thomas Spriggs. 2021-12-03. Spectral reconstruction in NRQCD via the Backus-Gilbert method. https://arxiv.org/abs/2112.02075

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