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Title: First measurement of target and double spin asymmetries for e-vectorp-vector{yields}ep{pi}{sup 0} in the nucleon resonance region above the {delta}(1232)

Journal Article · · Physical Review. C, Nuclear Physics
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  1. Fairfield University, Fairfield, Connecticut 06824 (United States)
  2. Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)

The exclusive channel p-vectore-vector,e{sup '}p){pi}{sup 0} was studied in the first and second nucleon resonance regions in the Q{sup 2} range from 0.187 to 0.770 GeV{sup 2} at Jefferson Lab using the CEBAF Large Acceptance Spectrometer. Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the {pi}{sup 0} and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes A{sub 1/2} and S{sub 1/2} for the Roper resonance N(1400)P{sub 11} and the N(1535)S{sub 11} and N(1520)D{sub 13} states.

OSTI ID:
21192342
Journal Information:
Physical Review. C, Nuclear Physics, Vol. 78, Issue 4; Other Information: DOI: 10.1103/PhysRevC.78.045204; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
Country of Publication:
United States
Language:
English