R. Fujita

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

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.

Improved search for two-neutrino double electron capture on 124Xe and 126Xe using particle identification in XMASS-I

We conducted an improved search for the simultaneous capture of two

Detectability of galactic supernova neutrinos coherently scattered on xenon nuclei in XMASS

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Search for solar Kaluza–Klein axions by annual modulation with the XMASS-I detector

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Direct dark matter search by annual modulation in XMASS-I

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A direct dark matter search in XMASS-I

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A measurement of the time profile of scintillation induced by low energy gamma-rays in liquid xenon with the XMASS-I detector

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Direct dark matter search by annual modulation with 2.7 years of XMASS-I data

Xe nuclei with emission of two neutrinos using 800.0 days of data from the XMASS-I detector. A novel method to discriminate

Development of low radioactivity photomultiplier tubes for the XMASS-I detector.

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Identification of 210Pb and 210Po in the bulk of copper samples with a low-background alpha particle counter

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