Quark-hadron duality and parity violating asymmetry of electroweak reactions in the {delta} region

Journal Article · Mon Aug 01 00:00:00 EDT 2005 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PhysRevC.72.025204· OSTI ID:20698928

Matsui, K; Sato, T ^[1]; Lee, T -S.H. ^[2]

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1. Department of Physics, Osaka University, Toyonaka, Osaka 560-0043 (Japan)
2. Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

A dynamical model [T. Sato and T.-S. H. Lee, Phys. Rev. C 54, 2660 (1996); 63, 055201 (2001); T. Sato, D. Uno, and T.-S. H. Lee, ibid. 67, 065201 (2003)] of electroweak pion production reactions in the {delta}(1232) region has been extended to include the neutral current contributions for examining the local quark-hadron duality in neutrino-induced reactions and for investigating how the axial N-{delta} form factor can be determined by the parity violating asymmetry of N(e{sup {yields}},e{sup '}) reactions. We first show that the recent data of (e,e{sup '}) structure functions F{sub 1} and F{sub 2}, which exhibit the quark-hadron duality, are in good agreement with our predictions. For possible future experimental tests, we then predict that the structure functions F{sub 1},F{sub 2}, and F{sub 3} for ({nu},e) and ({nu},{nu}{sup '}) processes also show the similar quark-hadron duality. The spin-dependent structure functions g{sub 1} and g{sub 2} of (e,e{sup '}) have also been calculated from our model. It is found that the local quark-hadron duality is not seen in the calculated g{sub 1} and g{sub 2}, while our results for g{sub 1} and some polarization observables associated with the exclusive p(e{sup {yields}},e{sup '}{pi}) and p{sup {yields}}(e{sup {yields}},e{sup '}{pi}) reactions are in reasonably good agreement with the recent data. In the study of parity violating asymmetry A of N(e{sup {yields}},e{sup '}) reactions, the relative importance between the nonresonant mechanisms and the {delta} excitation is investigated by taking into account the unitarity condition. Predictions are made for using the data of A to test the axial N-{delta} form factors determined previously in the studies of N({nu}{sub {mu}},{mu}{sup -}{pi}) reactions. The predicted asymmetry A are also compared with the parton model predictions for future experimental investigations of quark-hadron duality.

• OSTI ID: 20698928
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 72, Issue 2; Other Information: DOI: 10.1103/PhysRevC.72.025204; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
DELTA-1232 BARYONS
ELECTRON REACTIONS
ELECTRONS
EXCITATION
FORM FACTORS
MUON NEUTRINOS
MUONS MINUS
NEUTRAL CURRENTS
NEUTRINO-NUCLEON INTERACTIONS
P INVARIANCE
PARITY
PARTICLE PRODUCTION
PARTON MODEL
POLARIZATION
POLARIZED BEAMS
PROTON REACTIONS
QUARK MODEL
QUARK-HADRON INTERACTIONS
SPIN
STRUCTURE FUNCTIONS
UNITARITY