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arXiv · 2312.05154

The $\Lambda(1405)$ from Lattice QCD: Determining the Finite-volume Spectra

John Bulava·Bárbara Cid-Mora·Andrew D. Hanlon·Ben Hörz·Daniel Mohler·Colin Morningstar·Joseph Moscoso·Amy Nicholson·Fernando Romero-López·Sarah Skinner·André Walker-Loud
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Abstract

This work presents technical details of determining the finite-volume energy spectra for the scattering amplitude of the coupled-channel $\pi\Sigma - \bar{K}N$ from lattice QCD data. The importance of reliably extracting such spectra lies in the crucial dependence of the hadronic scattering amplitudes analysis on the energy spectrum when using L\"{u}scher's formalism. Results of the methods used are presented and the final finite-volume spectra are shown. The analysis of the scattering amplitude based on these results, exhibits a two-pole structure for the $\Lambda(1405)$, a virtual bound state below the $\pi\Sigma$ threshold and a resonance pole right below the $\bar{K}N$ threshold.

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John Bulava, Bárbara Cid-Mora, Andrew D. Hanlon, Ben Hörz, Daniel Mohler, Colin Morningstar, Joseph Moscoso, Amy Nicholson, Fernando Romero-López, Sarah Skinner, André Walker-Loud. 2023-12-08. The $\Lambda(1405)$ from Lattice QCD: Determining the Finite-volume Spectra. https://doi.org/10.22323/1.453.0131

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