First search for \(\alpha \) decays of naturally occurring Hf nuclides with emission of \(\gamma \) quanta

  • F. A. DanevichEmail author
  • M. Hult
  • D. V. Kasperovych
  • G. P. Kovtun
  • K. V. Kovtun
  • G. Lutter
  • G. Marissens
  • O. G. Polischuk
  • S. P. Stetsenko
  • V. I. Tretyak
Regular Article - Experimental Physics


The first ever search for \(\alpha \) decays to the first excited state in Yb was performed for six isotopes of hafnium (174, 176, 177, 178, 179, 180) using a high purity Hf sample of natural isotopic abundance with a mass of 179.8 g. For \(^{179}\)Hf, also \(\alpha \) decay to the ground state of \(^{175}\)Yb was searched for thanks to the \(\beta \)-instability of the daughter nuclide \(^{175}\)Yb. The measurements were conducted using an ultra-low-background HPGe-detector system located 225 m underground. After 75 days of data taking no decays were detected but lower bounds for the half-lives of the decays were derived on the level of \(\lim T_{1/2}\sim 10^{15}{-}10^{18}\) a. The decay with the shortest half-life based on theoretical calculation is the decay of \(^{174}\)Hf to the first \(2^+\) 84.3 keV excited level of \(^{170}\)Yb. The experimental lower bound was found to be \(T_{1/2}\ge 3.3\times 10^{15}\) a.



This project received support from the EC-JRC open access project EUFRAT under Horizon2020. The group from the Institute for Nuclear Research (Kyiv, Ukraine) was supported in part by the program of the National Academy of Sciences of Ukraine “Fundamental research on high-energy physics and nuclear physics (international cooperation)”. D.V.K. and O.G.P. were supported in part by the project “Investigations of rare nuclear processes” of the program of the National Academy of Sciences of Ukraine “Laboratory of young scientists” (Grant No. 0118U002328).


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Copyright information

© Società Italiana di Fisica (SIF) and Springer-Verlag GmbH Germany, part of Springer Nature 2020

Authors and Affiliations

  • F. A. Danevich
    • 1
    Email author
  • M. Hult
    • 2
  • D. V. Kasperovych
    • 1
  • G. P. Kovtun
    • 3
    • 4
  • K. V. Kovtun
    • 5
  • G. Lutter
    • 2
  • G. Marissens
    • 2
  • O. G. Polischuk
    • 1
  • S. P. Stetsenko
    • 3
  • V. I. Tretyak
    • 1
  1. 1.Institute for Nuclear ResearchKyivUkraine
  2. 2.European Commission, Joint Research CentreGeelBelgium
  3. 3.National Scientific Center Kharkiv Institute of Physics and TechnologyKharkivUkraine
  4. 4.Karazin Kharkiv National UniversityKharkivUkraine
  5. 5.Public Enterprise “Scientific and Technological Center Beryllium”KharkivUkraine

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