TY  - JOUR
AU  - Yao, D. L.
AU  - Alvarez-Ruso, L.
AU  - Vicente Vacas, M. J.
PY  - 2017
DA  - 2017//
TI  - Extraction of nucleon axial charge and radius from lattice QCD results using baryon chiral perturbation theory
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 116022
EP  - 11pp
VL  - 96
IS  - 11
PB  - Amer Physical Soc
AB  - We calculate the nucleon axial form factor up to the leading one-loop order in a covariant chiral effective field theory with the Delta(1232) resonance as an explicit degree of freedom. We fit the axial form factor to the latest lattice QCD data and pin down the relevant low-energy constants. The lattice QCD data, for various pion masses below 400 MeV, can be well described up to a momentum transfer of similar to 0.6 GeV. The Delta(1232) loops contribute significantly to this agreement. Furthermore, we extract the axial charge and radius based on the fitted values of the low-energy constants. The results are g(A) = 1.237(74) and < r(A)(2)> = 0.263(38) fm(2). The obtained coupling g(A) is consistent with the experimental value if the uncertainty is taken into account. The axial radius is below but in agreement with the recent extraction from neutrino quasielastic scattering data on deuterium, which has large error bars. Up to our current working accuracy, r(A) is predicted only at leading order, i.e., the one-loop level. A more precise determination might need terms of O(p(5)).
SN  - 2470-0010
UR  - http://arxiv.org/abs/1708.08776
UR  - https://doi.org/10.1103/PhysRevD.96.116022
DO  - 10.1103/PhysRevD.96.116022
LA  - English
N1  - WOS:000418917900010
ID  - Yao_etal2017
ER  -