Published September 2004 | Version v1
Journal article Metadata-only

γ*NΔ form factors from a relativistic dynamical model of pion electroproduction

Creators

  • 1. Institute of Nuclear and Particle Physics (INPP), Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States)
  • 2. Theory Group, Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606 (United States)
  • 3. Department of Physics, The College of William and Mary, Williamsburg, Virginia 23188 (United States)
  • 4. Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)

Description

We obtain the electromagnetic form factors of the γNΔ transition by analyzing recent pion-electroproduction data using a fully relativistic dynamical model. Special care is taken to satisfy Ward-Takahashi identities for the Born term in the presence of form factors, thereby allowing the use of realistic electromagnetic form factors of the nucleon and pion. We parametrize the Q2 dependence of the bare γNΔ form factors by a three-parameter form which is consistent with the asymptotic behavior inferred from QCD. The parameters of the bare γNΔ form factors are the only free parameters of the model and are fitted to the differential cross-section and multipole-analysis data up to Q2=4(GeV/c)2 in the Δ(1232)-resonance region. This analysis emphasizes the significance of the pion-cloud effects in the extraction of the resonance parameters

Additional details

Identifiers

DOI
10.1103/PhysRevC.70.032201;
arXiv
arXiv:nucl-th/0407069v2;

Publishing Information

Journal Title
Physical Review. C, Nuclear Physics
Journal Volume
70
Journal Issue
3
Journal Page Range
p. 032201-032201.5
ISSN
0556-2813
CODEN
PRVCAN

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
37011407
Subject category
S73: NUCLEAR PHYSICS AND RADIATION PHYSICS; S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
Descriptors DEI
DELTA-1232 BARYONS; DIFFERENTIAL CROSS SECTIONS; ELECTROMAGNETIC FORM FACTORS; ELECTROPRODUCTION; FOUR MOMENTUM TRANSFER; GEV RANGE; N BARYONS; NUCLEONS; PIONS; QUANTUM CHROMODYNAMICS; RELATIVISTIC RANGE; RESONANCE PARTICLES
Descriptors DEC
BARYONS; BASIC INTERACTIONS; BOSONS; CROSS SECTIONS; DELTA BARYONS; DIMENSIONLESS NUMBERS; ELECTROMAGNETIC INTERACTIONS; ELEMENTARY PARTICLES; ENERGY RANGE; FERMIONS; FIELD THEORIES; FORM FACTORS; HADRONS; INTERACTIONS; MESONS; MOMENTUM TRANSFER; N*BARYONS; PARTICLE INTERACTIONS; PARTICLE PRODUCTION; PARTICLE PROPERTIES; PSEUDOSCALAR MESONS; QUANTUM FIELD THEORY

Optional Information

Notes
(c) 2004 The American Physical Society