Chiral extrapolation of g_A with explicit Delta(1232) degrees of freedom

Abstract

An updated and extended analysis of the quark mass dependence of the nucleon's axial vector coupling constant g_A is presented in comparison with state-of-the-art lattice QCD results. Special emphasis is placed on the role of the Delta(1232) isobar. It is pointed out that standard chiral perturbation theory of the pion-nucleon system at order p^4 fails to provide an interpolation between the lattice data and the physical point. In constrast, a version of chiral effective field theory with explicit inclusion of the Delta(1232) proves to be successful. Detailed error analysis and convergence tests are performed. Integrating out the Delta(1232) as an explicit degree of freedom introduces uncontrolled errors for pion masses m_pi >~ 300 MeV.

25 pages, 12 figures, 2 tables; v2: minor changes

References in corpus (4)

• Nucleon mass: from lattice QCD to the chiral limit
• Convergence of the chiral expansion for the nucleon mass
• Lattice QCD with light Wilson quarks
• Chiral extrapolations

Cited by in corpus (9)

• In-medium chiral condensate beyond linear density approximation
• Nucleon structure with two flavors of dynamical domain-wall fermions
• The pion mass dependence of the nucleon form-factors of the energy momentum tensor in the chiral quark-soliton model
• Hyperon Axial Charges in Two-Flavor Chiral Perturbation Theory
• Chiral symmetry and the axial nucleon to Delta(1232) transition form factors
• Chiral Corrections to Hyperon Axial Form Factors
• Calculation of the axial charge in the epsilon and epsilon' regimes of HBChPT
• Dependence of nucleon properties on pseudoscalar meson masses
• Chiral corrections to the vector and axial couplings of quarks and baryons