Neutrinoless double beta decay in seesaw models
2010 (English)In: Journal of High Energy Physics (JHEP), ISSN 1029-8479, E-ISSN 1126-6708, Vol. 7Article in journal (Refereed) Published
We study the general phenomenology of neutrinoless double beta decay in seesaw models. In particular, we focus on the dependence of the neutrinoless double beta decay rate on the mass of the extra states introduced to account for the Majorana masses of light neutrinos. For this purpose, we compute the nuclear matrix elements as functions of the mass of the mediating fermions and estimate the associated uncertainties. We then discuss what can be inferred on the seesaw model parameters in the different mass regimes and clarify how the contribution of the light neutrinos should always be taken into account when deriving bounds on the extra parameters. Conversely, the extra states can also have a significant impact, canceling the Standard Model neutrino contribution for masses lighter than the nuclear scale and leading to unobservable neutrinoless double beta decay amplitudes even if neutrinos are Majorana particles. In particular, the decay rate is reduced by at least six orders of magnitude for masses of the extra states below 1MeV in absence of extra contributions. We also discuss how seesaw models could reconcile large rates of neutrinoless double beta decay with more stringent cosmological bounds on neutrino masses.
Place, publisher, year, edition, pages
2010. Vol. 7
Beyond Standard Model, Neutrino Physics
IdentifiersURN: urn:nbn:se:kth:diva-107139DOI: 10.1007/JHEP07(2010)096ISI: 000281504500095OAI: oai:DiVA.org:kth-107139DiVA: diva2:574751
QC 201305132012-12-062012-12-062013-05-13Bibliographically approved