An Effective-Field-Theory Analysis of Low-energy Parity Violation in the NN System

At low energies, parity violation in NN scattering (including photons) is described by an effective field theory (EFT) that includes only contact interactions. I will discuss this EFT, and its application to observables that would be zero in the absence of parity violation: longitudinal asymmetries in polarized nucleon-nucleon scattering, and asymmetries arising from polarized $\vec n p \rightarrow d \gamma$ and $np \rightarrow d \vec {\gamma}$.