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arXiv · 1806.01152

Search for Variations of Po-213 Half-Life

E. N. Alexeyev·Yu. M. Gavrilyuk·A. M. Gangapshev·A. M. Gezhaev·V. V. Kazalov·V. V. Kuzminov·S. I. Panasenko·S. S. Ratkevich
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Abstract

A device with the parent $^{229}$Th source was constructed to search for variations of the daughter $^{213}$Po half-life ($T_{1/2} = 4.2$ $μ$s). A solar-daily variation with amplitude $A_{So}=(5.3 \pm 1.1) \times 10^{-4}$, a lunar-daily variation with amplitude $A_L = (4.8 \pm 2.1) \times 10^{-4}$, and a sidereal-daily variation with amplitude $A_S = (4.2 \pm 1.7) \times 10^{-4}$ were found upon proceeding the data series over a 622-day interval (from July 2015 to March 2017). The $^{213}$Po half-life mean value is found to be $T_{1/2} = 3.705 \pm 0.001$ $μ$s. The obtained half-life is in good agreement with some of the literature values obtained with great accuracy.

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E. N. Alexeyev, Yu. M. Gavrilyuk, A. M. Gangapshev, A. M. Gezhaev, V. V. Kazalov, V. V. Kuzminov, S. I. Panasenko, S. S. Ratkevich. 2018-06-18. Search for Variations of Po-213 Half-Life. https://doi.org/10.1134/s1063779618040044

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