15th International Conference on Topics in Astroparticle and Underground Physics, TAUP2017

The nEXO radioassay program

Not scheduled

5m

Alumni Hall

Poster Neutrinos Poster Session

Speaker

Prof. Ryan MacLellan (University of South Dakota)

Description

The two neutrino double-beta decay of ${}^{136}$Xe, with a half-life of $2.165\pm 0.016\text{(stat.)}\pm 0.059\text{(syst.)}\times {10}^{21}$y, is among the rarest nuclear processes ever directly observed. The hypothesized neutrinoless double-beta decay of ${}^{136}$Xe, which nEXO aims to observe, is expected to be that much rarer, with a half-life of at least $1\times {10}^{26}$y at 90% C.L. Sufficient suppression of backgrounds is, therefore, crucial to making a discovery possible. The bulk of these backgrounds for nEXO are expected to result from radioactivity in the detector components. Reducing this background contribution to a sufficiently low level requires a comprehensive material screening program. This poster describes the techniques the nEXO Collaboration employs, built on the highly successful program developed by EXO-200, in the assay of candidate materials for nEXO components. A summary of recently released results of these efforts will also be presented.