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DOE OSTI · 2406880

Low-lying baryon resonances from lattice QCD

Bulava, John·Cid-Mora, Barbara·Hanlon, Andrew D.·Horz, Ben·Mohler, Daniel·Morningstar, Colin·Moscoso, Joseph·Nicholson, Amy·Romero-Lopez, Fernando·Skinner, Sarah·Walker-Loud, Andre
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Abstract

Recent results studying the masses and widths of low-lying baryon resonances in lattice QCD are presented. The S-wave Nπ scattering lengths for both total isospins I = 1/2 and I = 3/2 are inferred from the finite-volume spectrum below the inelastic threshold together with the I = 3/2 P-wave containing the Δ(1232) resonance. A lattice QCD computation employing a combined basis of three-quark and meson-baryon interpolating operators with definite momentum to determine the coupled channel $Σπ-N\bar{K}$ scattering amplitude in the Λ(1405) region is also presented. Our results support the picture of a two-pole structure suggested by theoretical approaches based on SU(3) chiral symmetry and unitarity.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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BibTeXRIS

Bulava, John, Cid-Mora, Barbara, Hanlon, Andrew D., Horz, Ben, Mohler, Daniel, Morningstar, Colin, Moscoso, Joseph, Nicholson, Amy, Romero-Lopez, Fernando, Skinner, Sarah, Walker-Loud, Andre. 2024-06-19. Low-lying baryon resonances from lattice QCD. https://doi.org/10.1393/ncc%2Fi2024-24165-1

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