0000000000514345

AUTHOR

B. Freehart

showing 3 related works from this author

Measurement of the $^{1}H$($\vec{\gamma}$, $\vec{p}$)$\pi^{0}$ reaction using a novel nucleon spin polarimeter

2013

We report the first large-acceptance measurement of polarization transfer from a polarized photon beam to a recoiling nucleon, pioneering a novel polarimetry technique with wide application to future nuclear and hadronic physics experiments. The commissioning measurement of polarization transfer in the $^{1}H$($\vec{\gamma}$,$\vec{p}$)$\pi^{0}$ reaction in the range $0.4<E_{\gamma}<1.4$ GeV is highly selective regarding the basic parameterizations used in partial wave analyses to extract the nucleon excitation spectrum. The new data strongly favor the recently proposed Chew-Mandelstam formalism.

Nuclear TheoryNuclear ExperimentNuclear Experiment
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Experimental study of theγp→ηpreaction with the Crystal Ball detector at the Mainz Microtron (MAMI-C)

2010

The gamma p - = W >= 1.87 GeV). Bremsstrahlung photons produced by the 1.5-GeV electron beam of the Mainz Microtron MAMI-C and momentum analyzed by the Glasgow tagging spectrometer were used for the eta-meson production. Our accumulation of 3.8 x 10(6) gamma p -< eta p -< 3 pi(0) p -< 6 gamma p events allows a detailed study of the reaction dynamics. The gamma p -< eta p differential cross sections were determined for 120 energy bins and the full range of the production angles. Our data show a dip near W = 1680 MeV in the total cross section caused by a substantial dip in eta production at forward angles. The data are compared to predictions of previous SAID and MAID partial-wave analyses a…

PhysicsNuclear and High Energy PhysicsMeson010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaPartial wave analysisHadronBremsstrahlung01 natural sciencesNuclear physicsParticle decay0103 physical sciencesNuclear Experiment010306 general physicsNucleonMicrotronCrystal BallPhysical Review C
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Measurement of theH1(γ⃗, p⃗)π0Reaction Using a Novel Nucleon Spin Polarimeter

2014

We report the first large-acceptance measurement of polarization transfer from a polarized photon beam to a recoiling nucleon. The measurement pioneers a novel polarimetry technique, which can be applied to many other nuclear and hadron physics experiments. The commissioning reaction of $^{1}H(\mathrm{\ensuremath{\gamma}P\vec},\text{ }\mathrm{pP\vec}){\ensuremath{\pi}}^{0}$ in the range $0.4l{E}_{\ensuremath{\gamma}}l1.4\text{ }\text{ }\mathrm{GeV}$ validates the technique and provides essential new data to constrain the excitation spectrum of the nucleon.

PhysicsParticle physicsMeson productionPartial wave analysisNuclear TheoryGeneral Physics and AstronomyPolarimeterPolarization (waves)7. Clean energyNuclear physicsHadron physicsPhoton beamNuclear ExperimentNucleonExcitationPhysical Review Letters
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