ASTROPHYSICAL AND TERRESTRIAL CONSTRAINTS ON SINGLET MAJORON MODELS

The general Lagrangian containing the couplings of the Higgs scalars t o Majorana neutrinos is presented in the context of singlet Majoron mo dels with intergenerational mixings. The analytical expressions for th e coupling of the Majoron field to charged fermions are derived within these models. Astrophysical considerations imply severe restrictions on the parameters of the three-generation Majoron model if the Dirac n eutrino mass matrix of the model follows a mass hierarchical pattern d ictated by grand unified theories. Bounds that originate from analyzin g possible charged lepton-violating decays in terrestrial experiments are also discussed. In particular, we find that experimental searches for muon decays by Majoron emission cannot generally be precluded by a strophysical requirements.