0000000000178043

AUTHOR

G. E. Dodge

showing 5 related works from this author

Virtual Compton scattering and the generalized polarizabilities of the proton atQ2=0.92and 1.76 GeV2

2012

Virtual Compton Scattering (VCS) on the proton has been studied at Jefferson Lab using the exclusive photon electroproduction reaction (e p --> e p gamma). This paper gives a detailed account of the analysis which has led to the determination of the structure functions P{sub LL}-P{sub TT}/epsilon and P{sub LT}, and the electric and magnetic generalized polarizabilities (GPs) alpha{sub E}(Q{sup 2}) and beta{sub M}(Q{sup 2}) at values of the four-momentum transfer squared Q{sup 2} = 0.92 and 1.76 GeV{sup 2}. These data, together with the results of VCS experiments at lower momenta, help building a coherent picture of the electric and magnetic GPs of the proton over the full measured Q{sup 2}-…

PhysicsNuclear and High Energy PhysicsParticle physicsPhotonChiral perturbation theoryProton010308 nuclear & particles physicsStructure functionCompton scattering01 natural sciencesNuclear physicsAmplitudeDispersion relation0103 physical sciencesBeta (velocity)010306 general physicsPhysical Review C
researchProduct

Precise Measurement of the Neutron Magnetic Form FactorGMnin the Few-GeV2Region

2009

The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q;{2}=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.

Physics010308 nuclear & particles physicsScatteringNuclear TheoryGeneral Physics and AstronomyScintillator7. Clean energy01 natural sciencesNuclear physicsDipoleDeuterium0103 physical sciencesMagnetic form factorNeutron detectionHigh Energy Physics::ExperimentNeutronNuclear Experiment010306 general physicsElectron scatteringPhysical Review Letters
researchProduct

Beam-Helicity Asymmetries in Double-Charged-Pion Photoproduction on the Proton

2005

Beam-helicity asymmetries for the two-pion-photoproduction reaction gamma + p --> p pi+ pi- have been studied for the first time in the resonance region for center-of-mass energies between 1.35 GeV and 2.30 GeV. The experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer using circularly polarized tagged photons incident on an unpolarized hydrogen target. Beam-helicity-dependent angular distributions of the final-state particles were measured. The large cross-section asymmetries exhibit strong sensitivity to the kinematics and dynamics of the reaction. The data are compared with the results of various phenomenological model calculations, and show that these…

Particle physicsPhotonProtonGeneral Physics and AstronomyFOS: Physical sciences13.60.-r 13.60.Le 13.88.+e[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)Pion0103 physical sciencesPhenomenological model[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear Experiment (nucl-ex)010306 general physicsNuclear ExperimentNuclear ExperimentPhysics010308 nuclear & particles physicsBremsstrahlungHelicity3. Good healthPair productionNucleon
researchProduct

Backward electroproduction ofπ0mesons on protons in the region of nucleon resonances at four momentum transfer squaredQ2=1.0GeV2

2004

Exclusive electroproduction of pi{sup 0} mesons on protons in the backward hemisphere has been studied at Q2 = 1.0 GeV2 by detecting protons in the forward direction in coincidence with scattered electrons from the 4 GeV electron beam in Jefferson Lab's Hall A. The data span the range of the total (gamma*p) center-of-mass energy W from the pion production threshold to W = 2.0 GeV. The differential cross sections sigma{sub T} + epsilon sigma{sub L}, sigma{sub TL}, and sigma{sub TT} were separated from the azimuthal distribution and are presented together with the MAID and SAID parameterizations.

PhysicsNuclear and High Energy PhysicsParticle physicsMeson010308 nuclear & particles physicsNuclear TheoryHadronMomentum transferSigma01 natural sciencesNuclear physicsBaryonPion0103 physical sciencesHigh Energy Physics::ExperimentNuclear Experiment010306 general physicsNucleonLeptonPhysical Review C
researchProduct

Virtual Compton Scattering and Neutral Pion Electroproduction in the Resonance Region up to the Deep Inelastic Region at Backward Angles

2009

We have made the first measurements of the virtual Compton scattering (VCS) process via the H$(e,e'p)\gamma$ exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the $W$-dependence at fixed $Q^2=1$ GeV$^2$, and for the $Q^2$-dependence at fixed $W$ near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed $Q^2$-dependence is smooth. The measured ratio of H$(e,e'p)\gamma$ to H$(e,e'p)\pi^0$ cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared to Real Compton Scattering (RCS) at high energy and large angles, our VCS data…

Elastic scatteringPhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsScatteringCompton scatteringResonanceFOS: Physical sciencesInelastic scattering[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]Deep inelastic scattering01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)Pion0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear Experiment (nucl-ex)010306 general physicsNucleonNuclear Experiment
researchProduct