Search for Variations of 213Ро Half-Life
A device with the parent 229Th source was constructed to search for variations of the daughter 213Po half-life (T1/2 = 4.2 μs). A solar-daily variation with amplitude ASo = (5.3 ± 1.1) × 10–4, a lunar-daily variation with amplitude AL = (4.8 ± 2.1) × 10–4, and a sidereal-daily variation with amplitude AS = (4.2 ± 1.7) × 10–4 were found upon proceeding the data series over a 622-day interval (from July 2015 to March 2017). The 213Po half-life mean value is found to be T1/2 = 3.705 ± 0.001 μs. The reference value is corrected by 12%.
Keywords:half-life 213Po nucleus daily and annual variations
The study was supported by the High Energy Physics and Neutrino Astrophysics Program of the Presidium of the Russian Academy of Sciences.
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