A Measurement of the Neutron Electric Form Factor in Dvec (evec,e'n)p Quasielastic Scattering at Q2=0.5(GeV/c)2

The form factors of the neutron give information on fundamental properties of the nucleons and provide a critical testing ground for models based on QCD. In late 1998, Jefferson Lab (JLAB) experiment E93-026 measured the spin-dependent part of the exclusive (e, e'n) scattering cross section from a polarized deuterated ammonia (15ND3) target at a four momentum transfer squared of Q2 = 0.5 (GeV/c)2. A longitudinally polarized electron beam was scattered from the polarized target and the quasi-elastically scattered electron was detected in coincidence with the knocked-out neutron. The data have been analyzed in terms of the spin-correlation parameter, or the electron-deuteron vector asymmetry (AedV), of (e, e'n) to determine the neutron electric form factor GEn. The result is consistent with data from existing experiments and shows a good agreement with the Galster parameterization of GEn within experimental uncertainty