Double beta decay searches of Xe-134, Xe-126 and Xe-124 with large scale Xe detectors

Abstract

The sensitivity for double beta decay studies of Xe-134 and Xe-124 is investigated assuming a potential large scale Xe experiment developed for dark matter searches depleted in Xe-136. The opportunity for an observation of the 2nu double beta decay of Xe-134 is explored for various scenarios. A positive observation should be possible for all calculated nuclear matrix elements. The detection of 2$\nu$ ECEC of Xe-124 can be probed in all scenarios covering the theoretical predicted half-life uncertainties and a potential search for Xe-126 is discussed. The sensitivity to beta+/EC decay of Xe-124 is discussed and a positive observation might be possible, while beta+/beta+ decay still remains unobservable. The performed studies take into account solar pp-neutrino interactions, $^{85}$Kr beta decay and remaining Xe-136 double beta decay as background components in the depleted detector.