Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English, Russian   Periodicity: 4 times per year   Open access peer reviewed journal

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P. Belli^1,2, R. Bernabei^1,2, R. S. Boiko^3,4, F. A. Danevich³, A. Di Marco^1,2, A. Incicchitti^5,6, D. V. Kasperovych³, F. Cappella⁵, V. Caracciolo⁷, V. V. Kobychev³, O. G. Polischuk³, N. V. Sokur^3,*, V. I. Tretyak³, R. Cerulli<sup>1,2

1</sup> INFN, Sezione di Roma “Tor Vergata”, Rome, Italy
² Dipartimento di Fisica, Universita di Roma “Tor Vergata”, Rome, Italy
³ Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine
⁴ National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine
⁵ INFN, Sezione di Roma, Rome, Italy
⁶ Dipartimento di Fisica, Universita di Roma “La Sapienza”, Rome, Italy
⁷ INFN, Laboratori Nazionali del Gran Sasso, Assergi, Italy

^*Corresponding author. E-mail address: nazar147@ukr.net

Abstract: Precise measurement of half-life of ²¹²Po (one of the daughter nuclides in radioactive chain of ²³²Th) was realized by means of liquid scintillator based on toluene doped by complex of thorium and trioctylphosphine oxide with concentration of Th ≈ 0.1 mass %. Fast photomultiplier tube and high frequency oscilloscope were used to acquire the scintillation signals waveforms. The algorithms were developed to find pairs of ²¹²Bi β-decays and subsequent ²¹²Po α-decays, to calculate time differences between the events in the pair, and to build ²¹²Bi β-decay and ²¹²Po α-decay energy spectra. Preliminary the ²¹²Po half-life is T_1/2 = (294.8 ± 1.9) ns. The experiment is in progress aiming at reduction of the statistical and systematic uncertainties.

Keywords: α-decay, ²¹²Po, half-life.

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