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arXiv · 2506.16161

Bayesian Analysis and Analytic Continuation of Scattering Amplitudes from Lattice QCD

Miguel Salg·Fernando Romero-López·William I. Jay
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Abstract

We present a novel procedure for analyzing the lattice-QCD spectrum via the finite-volume formalism to obtain constraints on multi-hadron scattering amplitudes at both real and complex energies. This approach combines a Bayesian reconstruction of the scattering amplitude on the real axis with Nevanlinna interpolation for analytic continuation to complex-valued energies. The method is non-parametric, inherently accounting for parametrization dependence within the uncertainty. We demonstrate the applicability of this approach using both toy data and real lattice-QCD data in resonant systems from the HadSpec and BaSc collaborations.

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BibTeXRIS

Miguel Salg, Fernando Romero-López, William I. Jay. 2025-06-19. Bayesian Analysis and Analytic Continuation of Scattering Amplitudes from Lattice QCD. https://arxiv.org/abs/2506.16161

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