Relativistic and nuclear structure effects in parity-violating quasielastic electron scattering

The parity-violating longitudinal asymmetry scrA is calculated for quasielastic electron scattering. We use a varietry of relativistic mean field models for the response of nuclear matter and C12 at a momentum transfer of q=550 MeV/c. Relativistic effects from a reduced nucleon mass, RPA correlations, and vacuum polarization can all change scrA by a relatively large amount. These large nuclear structure corrections could make it impossible to extract strange quark matrix elements or radiative corrections to weak axial currents.