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Title: Dispersion analysis of the nucleon form factors including meson continua

Abstract

Dispersion relations provide a powerful tool to analyze the electromagnetic form factors of the nucleon for all momentum transfers. Constraints from meson-nucleon scattering data, unitarity, and perturbative quantum chromodynamics (QCD) can be included in a straightforward way. In particular, we include the 2{pi},{rho}{pi}, and KK continua as independent input in our analysis and provide an error band for our results. Moreover, we discuss two different methods to include the asymptotic constraints from perturbative QCD. We simultaneously analyze the world data for all four form factors in both the spacelike and timelike regions and generally find good agreement with the data. We also extract the nucleon radii and the {omega}NN coupling constants. For the radii, we generally find good agreement with other determinations with the exception of the electric charge radius of the proton, which comes out smaller. The {omega}NN vector coupling constant is determined relatively well by the fits, but for the tensor coupling constant even the sign cannot be determined.

Authors:
; ;  [1];  [2]
  1. Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie), Universitaet Bonn, Nussallee 14-16, D-53115 Bonn (Germany)
  2. (Theorie), Universitaet Bonn, Nussallee 14-16, D-53115 Bonn (Germany) and Institut fuer Kernphysik (Theorie), Forschungszentrum Juelich, D-52425 Juelich (Germany)
Publication Date:
OSTI Identifier:
20995161
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevC.75.035202; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COUPLING CONSTANTS; DISPERSION RELATIONS; DISPERSIONS; ELECTRIC CHARGES; ELECTROMAGNETIC FORM FACTORS; MESON-NUCLEON INTERACTIONS; MESONS; MOMENTUM TRANSFER; PROTONS; QUANTUM CHROMODYNAMICS

Citation Formats

Belushkin, M. A., Hammer, H.-W., Meissner, Ulf-G., and Helmholtz-Institut fuer Strahlen- und Kernphysik. Dispersion analysis of the nucleon form factors including meson continua. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.035202.
Belushkin, M. A., Hammer, H.-W., Meissner, Ulf-G., & Helmholtz-Institut fuer Strahlen- und Kernphysik. Dispersion analysis of the nucleon form factors including meson continua. United States. doi:10.1103/PHYSREVC.75.035202.
Belushkin, M. A., Hammer, H.-W., Meissner, Ulf-G., and Helmholtz-Institut fuer Strahlen- und Kernphysik. Thu . "Dispersion analysis of the nucleon form factors including meson continua". United States. doi:10.1103/PHYSREVC.75.035202.
@article{osti_20995161,
title = {Dispersion analysis of the nucleon form factors including meson continua},
author = {Belushkin, M. A. and Hammer, H.-W. and Meissner, Ulf-G. and Helmholtz-Institut fuer Strahlen- und Kernphysik},
abstractNote = {Dispersion relations provide a powerful tool to analyze the electromagnetic form factors of the nucleon for all momentum transfers. Constraints from meson-nucleon scattering data, unitarity, and perturbative quantum chromodynamics (QCD) can be included in a straightforward way. In particular, we include the 2{pi},{rho}{pi}, and KK continua as independent input in our analysis and provide an error band for our results. Moreover, we discuss two different methods to include the asymptotic constraints from perturbative QCD. We simultaneously analyze the world data for all four form factors in both the spacelike and timelike regions and generally find good agreement with the data. We also extract the nucleon radii and the {omega}NN coupling constants. For the radii, we generally find good agreement with other determinations with the exception of the electric charge radius of the proton, which comes out smaller. The {omega}NN vector coupling constant is determined relatively well by the fits, but for the tensor coupling constant even the sign cannot be determined.},
doi = {10.1103/PHYSREVC.75.035202},
journal = {Physical Review. C, Nuclear Physics},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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