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Limits RegistryThe XENON1T dark-matter detector at Italy's Gran Sasso laboratory observed two-neutrino double electron capture in xenon-124 and measured its half-life as 1.8x10^22 years, about a trillion times the age of the universe. Published in Nature in April 2019, it is the slowest process ever directly observed.
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The XENON1T dark-matter detector at Italy's Gran Sasso laboratory observed two-neutrino double electron capture in xenon-124 and measured its half-life as 1.8x10^22 years, about a trillion times the age of the universe. Published in Nature in April 2019, it is the slowest process ever directly observed.
The longest half-life of a nuclear decay process whose individual decay events were directly detected and counted.
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Limits Registry. LR-LONGEST-HALF-LIFE-DIRECTLY-OBSERVED. Longest half-life ever directly observed (xenon-124). 2026.