Shell Model Studies of Competing Mechanisms to the Neutrinoless Double-Beta Decay in 124Sn, 130Te, and 136Xe

Abstract EN

Neutrinoless double-beta decay is a predicted beyond Standard Model process that could clarify some of the not yet known neutrino properties, such as the mass scale, the mass hierarchy, and its nature as a Dirac or Majorana fermion.

Should this transition be observed, there are still challenges in understanding the underlying contributing mechanisms.

We perform a detailed shell model investigation of several beyond Standard Model mechanisms that consider the existence of right-handed currents.

Our analysis presents different venues that can be used to identify the dominant mechanisms for nuclei of experimental interest in the mass A~130 region (124Sn, 130Te, and 136Xe).

It requires accurate knowledge of nine nuclear matrix elements that we calculate in addition to the associated energy-dependent phase space factors.