Polarized Electron-Electron Scattering at GeV Energies

Abstract

The longitudinal polarization of the new Yale University-Stanford Linear Accelerator Center polarized-electron beam has been determined at laboratory energies between 6.47 and 19.40 GeV. Spin-dependent elastic electron-electron scattering (M\o{}ller scattering) has been found to be a practical technique for polarization measurements at high energies. The results are consistent with the energy and angular dependence predicted by quantum electrodynamics and with an energy-independent beam polarization of 0.76\ifmmode\pm\else\textpm\fi{}0.03.