A general parametrization for the long-range part of neutrinoless double beta decay

Double beta decay has been proven to be a powerful tool to constrain $B-L$ violating physics beyond the standard model. We present a representation for the long-range part of the general $0\nu \beta \beta$ decay rate allowed by Lorentz-invariance. Combined with the short range part this general parametrization in terms of effective $B-L$ violating couplings will provide the $0\nu \beta \beta$ limits on arbitrary lepton number violating theories.