Search for neutrino-less double beta decay with EXO-200 and prospects for Ba ion tagging

Abstract

The Enriched Xenon Observatory collaboration searches for neutrino-less double beta decay in 136Xe. The first phase of the experiment, EXO-200 has started taking data in 2011 and has already produced important physics results like the first observation of the allowed two-neutrino double beta decay in 136Xe. A massive effort for material screening has accompanied the design of EXO-200 and has produced a detector with very low background due to the residual radioactivity. The most recent data analysis campaign has provided a strong limit for the neutrino-less double beta decay in 136Xe. For the next phase ton-scale detector, the collaboration is investigating the options for employing a Ba ion tagging technique to provide complete suppression of the radioactive background.