Constraints on lepton number violating short-range interactions from |ΔL| = 2 processes

In this work we study the short-range contributions that induce effective lepton number violating (LNV) interactions. We obtain a full set of constraints on the effective short-range couplings from a large variety of low-energy |ΔL|=2 processes of pseudoscalar mesons K,D,Ds,B, and τ-lepton. These constraints provide complementary and additional information to the one obtained from the neutrinoless double-β (0νββ) decay. As expected, the bounds on electron-electron short-range couplings are the only ones that are strongly constrained by the 0νββ decay. Although weaker, LNV effective couplings with different flavors are not accessible to 0νββ decay and these can be probe by the |ΔL|=2 processes in consideration.