6533b85cfe1ef96bd12bd316

RESEARCH PRODUCT

First measurement of the electric formfactor of the neutron in the exclusive quasielastic scattering of polarized electrons from polarized 3He

K.-h. SteffensJ. D. KellieS.j. HallL.d. SchearerS. PlützerE. ReichertWerner HeilJ. Blume-werryTh. DomboH. G. AndresenErnst W. OttenP. GrabmayrCh. NachtigallDaniela RoheR.o. OwensH. SchmiedenT. HehlM. SchäferP. HartmannJ. HoffmannMichèle LeducF. KleinA. FreyH. FischerReinhard SurkauM. OstrickJ. BeckerD. EylM. MeyerhoffK. AulenbacherTh. WalcherJ. E. DucretP. DrescherH. MöllerJrm Annand

subject

Nuclear reactionPhysicsNuclear and High Energy PhysicsQuasielastic scatteringScatteringmedia_common.quotation_subjectElectric form factorElectronPolarization (waves)AsymmetryCoincidenceNuclear physicsQuasielastic neutron scatteringNeutronAtomic physicsNucleonMicrotronmedia_common

description

Abstract A first measurement of the asymmetry in quasielastic scattering of longitudinally polarized electrons from a polarized 3 He gas target in coincidence with the knocked out neutron is reported. This measurement was made feasible by the cw beam of the 855 MeV Mainz Microtron MAMI. It allows a determination of the electric formfactor of the neutron G E n independent of binding effects to first order. At Q 2 =0.31 ( GeV /c) 2 two asymmetries A ∥ ( S He ∥ q ) and A ⊥ ( S He ⊥ q ) have been measured giving A ∥ =(−7.40±0.73)% and A ⊥ =(0.89±0.30)% . The ratio A ⊥ / A ∥ is independent of the absolute value of the electron and target polarization and yields G E n =0.035±0.012±0.005.

https://doi.org/10.1063/1.48494