Axial, induced pseudoscalar, and pionnucleon form factors in manifestly Lorentzinvariant chiral perturbation theory
Abstract
We calculate the nucleon form factors G{sub A} and G{sub P} of the isovector axialvector current and the pionnucleon form factor G{sub {pi}}{sub N} in manifestly Lorentzinvariant baryon chiral perturbation theory up to and including order O(p{sup 4}). In addition to the standard treatment including the nucleon and pions, we also consider the axialvector meson a{sub 1} as an explicit degree of freedom. This is achieved by using the reformulated infrared renormalization scheme. We find that the inclusion of the axialvector meson effectively results in one additional lowenergy coupling constant that we determine by a fit to the data for G{sub A}. The inclusion of the axialvector meson results in an improved description of the experimental data for G{sub A}, while the contribution to G{sub P} is small.
 Authors:
 Institut fuer Kernphysik, Johannes GutenbergUniversitaet, D55099 Mainz (Germany)
 (United States)
 Publication Date:
 OSTI Identifier:
 20991038
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevC.75.025202; (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; AXIAL VECTOR MESONS; AXIALVECTOR CURRENTS; CHIRALITY; FORM FACTORS; INCLUSIONS; ISOVECTORS; LORENTZ INVARIANCE; NUCLEONS; PERTURBATION THEORY; PIONS
Citation Formats
Schindler, M. R., Fuchs, T., Scherer, S., Gegelia, J., and High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia. Axial, induced pseudoscalar, and pionnucleon form factors in manifestly Lorentzinvariant chiral perturbation theory. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVC.75.025202.
Schindler, M. R., Fuchs, T., Scherer, S., Gegelia, J., & High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia. Axial, induced pseudoscalar, and pionnucleon form factors in manifestly Lorentzinvariant chiral perturbation theory. United States. doi:10.1103/PHYSREVC.75.025202.
Schindler, M. R., Fuchs, T., Scherer, S., Gegelia, J., and High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia. Thu .
"Axial, induced pseudoscalar, and pionnucleon form factors in manifestly Lorentzinvariant chiral perturbation theory". United States.
doi:10.1103/PHYSREVC.75.025202.
@article{osti_20991038,
title = {Axial, induced pseudoscalar, and pionnucleon form factors in manifestly Lorentzinvariant chiral perturbation theory},
author = {Schindler, M. R. and Fuchs, T. and Scherer, S. and Gegelia, J. and High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia},
abstractNote = {We calculate the nucleon form factors G{sub A} and G{sub P} of the isovector axialvector current and the pionnucleon form factor G{sub {pi}}{sub N} in manifestly Lorentzinvariant baryon chiral perturbation theory up to and including order O(p{sup 4}). In addition to the standard treatment including the nucleon and pions, we also consider the axialvector meson a{sub 1} as an explicit degree of freedom. This is achieved by using the reformulated infrared renormalization scheme. We find that the inclusion of the axialvector meson effectively results in one additional lowenergy coupling constant that we determine by a fit to the data for G{sub A}. The inclusion of the axialvector meson results in an improved description of the experimental data for G{sub A}, while the contribution to G{sub P} is small.},
doi = {10.1103/PHYSREVC.75.025202},
journal = {Physical Review. C, Nuclear Physics},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}

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