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Title: Axial, induced pseudoscalar, and pion-nucleon form factors in manifestly Lorentz-invariant chiral perturbation theory

Abstract

We calculate the nucleon form factors G{sub A} and G{sub P} of the isovector axial-vector current and the pion-nucleon form factor G{sub {pi}}{sub N} in manifestly Lorentz-invariant 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 axial-vector 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 axial-vector meson effectively results in one additional low-energy coupling constant that we determine by a fit to the data for G{sub A}. The inclusion of the axial-vector meson results in an improved description of the experimental data for G{sub A}, while the contribution to G{sub P} is small.

Authors:
; ;  [1];  [1];  [2]
  1. Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany)
  2. (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; AXIAL-VECTOR 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 pion-nucleon form factors in manifestly Lorentz-invariant 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 pion-nucleon form factors in manifestly Lorentz-invariant 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 pion-nucleon form factors in manifestly Lorentz-invariant chiral perturbation theory". United States. doi:10.1103/PHYSREVC.75.025202.
@article{osti_20991038,
title = {Axial, induced pseudoscalar, and pion-nucleon form factors in manifestly Lorentz-invariant 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 axial-vector current and the pion-nucleon form factor G{sub {pi}}{sub N} in manifestly Lorentz-invariant 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 axial-vector 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 axial-vector meson effectively results in one additional low-energy coupling constant that we determine by a fit to the data for G{sub A}. The inclusion of the axial-vector 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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