Search for two-neutrino double electron capture on 124Xe with the XMASS-I detector

Year: 2016

Type: article

Abstract: Double electron capture is a rare nuclear decay process in which two orbital electrons are captured simultaneously in the same nucleus. Measurement of its two-neutrino mode would provide a new reference for the calculation of nuclear matrix elements whereas observation of its neutrinoless mode would demonstrate lepton number violation. A search for two-neutrino double electron capture on 124 Xe is performed using 165.9 days of data collected with the XMASS-I liquid xenon detector. No significant excess above background was observed and we set a lower limit on the half-life as 4.7 × 10 21 years at 90% confidence level. The obtained limit has ruled out parts of some theoretical expectations. We obtain a lower limit on the 126 Xe two-neutrino double electron capture half-life of 4.3 × 10 21 years at 90% confidence level as well.

Source: Physics Letters B

DOI: 10.1016/j.physletb.2016.05.039

Institutions: Kavli Institute for the Physics and Mathematics of the Universe, Institute for Cosmic Ray Research, Kamioka Observatory, The University of Tokyo, Institute for Basic Science, Gifu University, Korea Research Institute of Standards and Science

Language: English

Topic: Neutrino Physics Research

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: diamond

Funders: Ministry of Education, Culture, Sports, Science and Technology, National Research Foundation of Korea, Japan Society for the Promotion of Science

Awards: G2396335199, Search for double beta decay of xenon by polyhedral approach, Study of Dark Matter, G416265900

OpenAlex ID: W2201689899