Chiral extrapolation of g{sub A} with explicit {delta}(1232) degrees of freedom
Abstract
An updated and extended analysis of the quarkmass dependence of the nucleon's axialvector coupling constant g{sub A} is presented in comparison with stateoftheart 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 pionnucleon system at order p{sup 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{sub {pi}} > or approx. 300 MeV.
 Authors:
 PhysikDepartment, Theoretische Physik, Technische Universitaet Muenchen, D85747 Garching (Germany)
 Publication Date:
 OSTI Identifier:
 20933245
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.75.014503; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRALITY; CONVERGENCE; COUPLING CONSTANTS; DEGREES OF FREEDOM; DELTA1232 BARYONS; ERRORS; EXTRAPOLATION; INTERPOLATION; MASS; MEV RANGE 1001000; NUCLEONS; PERTURBATION THEORY; PIONNUCLEON INTERACTIONS; PIONS; QUANTUM CHROMODYNAMICS; QUARKS
Citation Formats
Procura, M., Musch, B. U., Hemmert, T. R., and Weise, W. Chiral extrapolation of g{sub A} with explicit {delta}(1232) degrees of freedom. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.014503.
Procura, M., Musch, B. U., Hemmert, T. R., & Weise, W. Chiral extrapolation of g{sub A} with explicit {delta}(1232) degrees of freedom. United States. doi:10.1103/PHYSREVD.75.014503.
Procura, M., Musch, B. U., Hemmert, T. R., and Weise, W. Mon .
"Chiral extrapolation of g{sub A} with explicit {delta}(1232) degrees of freedom". United States.
doi:10.1103/PHYSREVD.75.014503.
@article{osti_20933245,
title = {Chiral extrapolation of g{sub A} with explicit {delta}(1232) degrees of freedom},
author = {Procura, M. and Musch, B. U. and Hemmert, T. R. and Weise, W.},
abstractNote = {An updated and extended analysis of the quarkmass dependence of the nucleon's axialvector coupling constant g{sub A} is presented in comparison with stateoftheart 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 pionnucleon system at order p{sup 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{sub {pi}} > or approx. 300 MeV.},
doi = {10.1103/PHYSREVD.75.014503},
journal = {Physical Review. D, Particles Fields},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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