Measurements of the Electric Form Factor of the Neutron up to Q²=3.4  GeV² Using the Reaction ³He⃗(e⃗,e′n)pp

The electric form factor of the neutron was determined from studies of the reaction ³He⃗(e⃗,e^′n)pp in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q² range over which it is known, we find G_Eⁿ=0.0236±0.0017(stat)±0.0026(syst), 0.0208±0.0024±0.0019, and 0.0147±0.0020±0.0014 for Q²=1.72, 2.48, and 3.41  GeV², respectively.