Majorons without majorana masses and neutrinoless double beta decay

We explain excess events near the endpoints of the double beta decay (ββ) spectra of several elements, using the neutrinoless emission of massless Goldstone bosons. Models with scalar carrying lepton number −2 are proposed for this purpose so that ordinary neutrinoless ββ is forbidden, and we can raise the scale of global symmetry breaking above the 10 keV scale needed for observable emission of conventional majorons in ββ. The electron …