Precision measurement of the proton electric to magnetic form factor ratio with BLAST

Abstract

We have measured ... in the South Hall Ring of the MIT-Bates Linear Accelerator Facility. This experiment used a polarized electron beam, a pure hydrogen internal polarized target, and the symmetric Bates Large Acceptance Spectrometer Toroid (BLAST) detector. By measuring the spin-dependent elastic ... asymmetry in both sectors simultaneously, we could extract the form factor ratio independent of beam and target polarization. This was the first experiment to measure ... using a polarized target, which is complementary to recoil polarimetry experiments.