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arXiv · 1812.10997

Half-life measurements of $^{212}$Po with thorium-loaded liquid scintillator

P. Belli·R. Bernabei·R. S. Boiko·F. A. Danevich·A. Di Marco·A. Incicchitti·D. V. Kasperovych·F. Cappella·V. Caracciolo·V. V. Kobychev·O. G. Polischuk·N. V. Sokur·V. I. Tretyak·R. Cerulli
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Abstract

Precise measurement of half-life of $^{212}$Po (one of the daughter nuclides in radioactive chain of $^{232}$Th) was realized by means of liquid scintillator based on toluene doped by complex of thorium and trioctylphosphine oxide with concentration of Th $\sim0.1$ mass %. Fast photomultiplier tube and high frequency oscilloscope were used to acquire the scintillation signals waveforms. The algorithms were developed to find pairs of $^{212}$Bi beta-decays and subsequent $^{212}$Po alpha-decays, to calculate time differences between the events in the pair, and to build $^{212}$Bi beta-decay and $^{212}$Po alpha-decay energy spectra. Preliminary the $^{212}$Po half-life is $T_{1/2} = (294.8 \pm 1.9)$ ns. The experiment is in progress aiming at reduction of the statistical and systematic uncertainties.

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P. Belli, R. Bernabei, R. S. Boiko, F. A. Danevich, A. Di Marco, A. Incicchitti, D. V. Kasperovych, F. Cappella, V. Caracciolo, V. V. Kobychev, O. G. Polischuk, N. V. Sokur, V. I. Tretyak, R. Cerulli. 2019-01-10. Half-life measurements of $^{212}$Po with thorium-loaded liquid scintillator. https://doi.org/10.15407/jnpae2018.03.220

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