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Title: {gamma}*N{delta} form factors from a relativistic dynamical model of pion electroproduction

Journal Article · · Physical Review. C, Nuclear Physics
;  [1];  [2];  [3]
  1. Institute of Nuclear and Particle Physics (INPP), Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States)
  2. Department of Physics, The College of William and Mary, Williamsburg, Virginia 23188 (United States)
  3. Theory Group, Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606 (United States)

We obtain the electromagnetic form factors of the {gamma}N{delta} 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 Q{sup 2} dependence of the bare {gamma}N{delta} form factors by a three-parameter form which is consistent with the asymptotic behavior inferred from QCD. The parameters of the bare {gamma}N{delta} form factors are the only free parameters of the model and are fitted to the differential cross-section and multipole-analysis data up to Q{sup 2}=4(GeV/c){sup 2} in the {delta}(1232)-resonance region. This analysis emphasizes the significance of the pion-cloud effects in the extraction of the resonance parameters.

OSTI ID:
20695497
Journal Information:
Physical Review. C, Nuclear Physics, Vol. 70, Issue 3; Other Information: DOI: 10.1103/PhysRevC.70.032201; (c) 2004 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
Country of Publication:
United States
Language:
English