Nucleon charges and σ -terms in lattice QCD

IF 5 2区物理与天体物理 Q1 Physics and Astronomy

Physical Review D Pub Date : 2025-03-10 DOI:10.1103/physrevd.111.054505

C. Alexandrou, S. Bacchio, J. Finkenrath, C. Iona, G. Koutsou, Y. Li, G. Spanoudes

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引用次数: 0

Abstract

We determine the nucleon axial, scalar, and tensor charges and the nucleon σ-terms using twisted mass fermions. We employ three ensembles with approximately equal physical volume of about 5.5 fm, three values of the lattice spacing, approximately 0.06, 0.07, and 0.08 fm, and with the mass of the degenerate up and down, strange and charm quarks tuned to approximately their physical values. We compute both isovector and isoscalar charges and σ-terms and their flavor decomposition including the disconnected contributions. We use the Akaike information criterion to evaluate systematic errors due to excited states and the continuum extrapolation. For the nucleon isovector axial charge we find gAu−d=1.250(24), in agreement with the experimental value. Moreover, we extract the nucleon σ-terms and find for the light quark content σπN=41.9(8.1) MeV and for the strange σs=30(17) MeV.

Published by the American Physical Society

2025

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来源期刊

Physical Review D 物理-天文与天体物理

CiteScore

9.20

自引率

36.00%

发文量

审稿时长

2 months

期刊介绍： Physical Review D (PRD) is a leading journal in elementary particle physics, field theory, gravitation, and cosmology and is one of the top-cited journals in high-energy physics. PRD covers experimental and theoretical results in all aspects of particle physics, field theory, gravitation and cosmology, including: Particle physics experiments, Electroweak interactions, Strong interactions, Lattice field theories, lattice QCD, Beyond the standard model physics, Phenomenological aspects of field theory, general methods, Gravity, cosmology, cosmic rays, Astrophysics and astroparticle physics, General relativity, Formal aspects of field theory, field theory in curved space, String theory, quantum gravity, gauge/gravity duality.