Discovering neutrinoless double beta decay with NEXT100 detector

NEXT is a new experiment to search for neutrinoless double beta decay processes that will start operation at the LSC laboratory (Canfranc, Spain) in 2013. The apparatus is a high pressure gas xenon chamber (HPGXe) filled with 100-150 kg of gas Xenon enriched at 90% in the 136Xe isotope. NEXT proposes a novel detection technique called SOFT (Separated Optimized Function TPC) which optimizes both the energy resolution and the measurement of the topological signature of the event. This results in a powerful background rejection, which, combined with a carefully screened radiopure detector will allow NEXT to be competitive with existing proposals for next-generation neutrinoless double-beta decay experiments. First prototypes have been operating successfully in different laboratories. First results with large-scale prototypes measure a resolution of 1% FWHM at the 137Cs photopeak. This extrapolates to a resolution better than 0.5% FWHM at Qββ.