Nuclear Physics and Atomic Energy

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
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Nucl. Phys. At. Energy 2018, volume 19, issue 3, pages 220-226.
Section: Nuclear Physics.
Received: 05.06.2018; Accepted: 11.10.2018; Published online: 04.12.2018.
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Half-life measurements of 212Po with thorium-loaded liquid scintillator

P. Belli1,2, R. Bernabei1,2, R. S. Boiko3,4, F. A. Danevich3, A. Di Marco1,2, A. Incicchitti5,6, D. V. Kasperovych3, F. Cappella5, V. Caracciolo7, V. V. Kobychev3, O. G. Polischuk3, N. V. Sokur3,*, V. I. Tretyak3, R. Cerulli1,2

1 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:

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 T1/2 = (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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