&Delta B = 2 nuclear effective field theory

We build an effective field theory (EFT) for a model-independent, systematic study of 2-unit baryon-number violation in the context of nuclear physics. This EFT has nucleon and antinucleon simultaneously as heavy baryons. As an illustration, we perform a calculation of the deuteron decay in next-to-leading order (NLO). We show that such decay is dominated by neutron-antineutron oscillation, other processes such as two-nucleon annihilation (NN -> mesons) appearing only beyond NLO.