Nuclear Physics and Atomic Energy

ядерна ф≥зика 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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Nucl. Phys. At. Energy 2016, volume 17, issue 1, pages 12-17.
Section: Nuclear Physics.
Received: 18.11.2015; Accepted: 11.04.2016; Published online: 02.06.2016.
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Energy and intensity of γ-transitions in the decay of 137Cs

V. T. Kupryashkin*

Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine

*Corresponding author. E-mail address:

Abstract: In order to verify the data from 137Cs decay, γ-spectrum was measured using the high-resolution detector with Compton background suppression. It was found that the transition γ279 keV, detected in a number of works, has not been observed and should be regarded as wrong. Evaluation of the intensity of γ279 keV in our work is Iγ < 7 ⋅ 10-7. Energy of the transition γ283.4(1) keV is in good agreement with previous works, as well as with data presented in the latest compilation of data on 137Cs. Intensity of transition γ283.4(1) keV, where data from different projects were significantly different from each other, is refined as Iγ = 67(20) ⋅ 10-7. Our evaluation of intensity of γ378 keV (Iγ < 6 ⋅ 10-7) confirms low intensity of recently discovered weak transition γ377.9 keV which comes from the 661.7 keV level to 283.5 keV level.

Keywords: 137Cs decay, γ spectra, γ rays intensity and energy, HPGe detector.


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