Abstract
The design changes of the Baksan low-background TAU-1 and TAU-2 set-ups allowed to improve a sensitivity of 214Po half-life (τ) measurements up to the 2.5 × 10−4 are described. Different possible sources of systematic errors influencing on the τ-value are studied. An annual variation of 214Po half-life time measurements with an amplitude of A = (6.9 ± 3) × 10−4 and a phase of φ = 93 ± 10 days was found in a sequence of the week-collected τ-values obtained from the TAU-2 data sample with total duration of 480 days. 24 hours’ variation of the t-value measurements with an amplitude of A = (10.0 ± 2.6) × 10−4 and phase of φ = 1 ± 0.5 hours was found in a solar day 1 hour step t-value sequence formed from the same data sample. It was found that the 214Po half-life averaged at 480 days is equal to 163.45 ± 0.04 μs.
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Talk at The International Workshop on Prospects of Particle Physics: “Neutrino Physics and Astrophysics” January 26–February 2, 2014, Valday, Russia.
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Alexeyev, E.N., Gavrilyuk, Y.M., Gangapshev, A.M. et al. Sources of the systematic errors in measurements of 214Po decay half-life time variations at the Baksan deep underground experiments. Phys. Part. Nuclei 46, 157–165 (2015). https://doi.org/10.1134/S1063779615020021
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DOI: https://doi.org/10.1134/S1063779615020021