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arXiv · 2305.17120

Sphaleron rate from a modified Backus-Gilbert inversion method

Claudio Bonanno·Francesco D'Angelo·Massimo D'Elia·Lorenzo Maio·Manuel Naviglio
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Abstract

We compute the sphaleron rate in quenched QCD for a temperature $T \simeq 1.24~T_c$ from the inversion of the Euclidean lattice time correlator of the topological charge density. We explore and compare two different strategies: one follows a new approach proposed in this study and consists in extracting the rate from finite lattice spacing correlators, and then in taking the continuum limit at fixed smoothing radius followed by a zero-smoothing extrapolation; the other follows the traditional approach of extracting the rate after performing such double extrapolation directly on the correlator. In both cases the rate is obtained from a recently-proposed modification of the standard Backus-Gilbert procedure. The two strategies lead to compatible estimates within errors, which are then compared to previous results in the literature at the same or similar temperatures; the new strategy permits to obtain improved results, in terms of statistical and systematic uncertainties.

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Claudio Bonanno, Francesco D'Angelo, Massimo D'Elia, Lorenzo Maio, Manuel Naviglio. 2023-05-26. Sphaleron rate from a modified Backus-Gilbert inversion method. https://arxiv.org/abs/2305.17120

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