Abstract
Results from a search for neutrinoless double-beta decay () of are presented using the first year of data taken with the upgraded EXO-200 detector. Relative to previous searches by EXO-200, the energy resolution of the detector has been improved to , the electric field in the drift region has been raised by 50%, and a system to suppress radon in the volume between the cryostat and lead shielding has been implemented. In addition, analysis techniques that improve topological discrimination between and background events have been developed. Incorporating these hardware and analysis improvements, the median 90% confidence level half-life sensitivity after combining with the full data set acquired before the upgrade has increased twofold to . No statistically significant evidence for is observed, leading to a lower limit on the half-life of at the 90% confidence level.
- Received 1 August 2017
- Revised 6 October 2017
DOI:https://doi.org/10.1103/PhysRevLett.120.072701
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Viewpoint
The Hunt for No Neutrinos
Published 26 March 2018
Four experiments have demonstrated new levels of sensitivity to neutrinoless double-beta decay, a process whose existence would prove that neutrinos are their own antiparticles.
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