Radiative corrections to the azimuthal asymmetry in transversely polarized Møller scattering

Experiment E158 at SLAC can measure an azimuthal asymmetry in single-spin, transversely polarized Møller scattering, $e^{-\uparrow }{e}^{-}\to e^{-}{e}^{-},$ which arises from a QED rescattering phase. We recompute the leading-order (one-loop) asymmetry, confirming previous results, and calculate the leading logarithmic QED corrections due to initial-state radiation from the beam and target electrons and due to final-state radiation. The size of these radiative corrections is quite sensitive to experimental details, such as the acceptance in energy and in polar angle of the scattered electron. For E158, the corrections are modest, increasing the parts-per-million asymmetry by roughly 1%.