On the possibility of destructive interference between light and heavy Majorana neutrinos in neutrinoless double beta decay

The possibility of destructive interference between the contributions from light and heavy Majorana neutrinos in the neutrinoless double beta decay amplitude is considered. Incorporating recent limits on the masses and mixing of heavy neutrinos coupled to the electron, it is found that destructive interference in tellurium can occur only if the heavy neutrino mass lies in the following regions: 20 MeV< or approx.m< or approx.30 MeV, 60 MeV< or approx.m< or approx.140 MeV, and 170 MeV< or approx.m< or approx.200 MeV. This greatly improves the previous estimate of m< or approx.3.5 GeV. A model is then described to illustrate how the destructive interference might occur. (orig.)