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
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Nucl. Phys. At. Energy 2023, volume 24, issue 3, pages 193-208.
Section: Nuclear Physics.
Received: 30.06.2023; Accepted: 28.07.2023; Published online: 20.09.2023.
PDF Full text (en)

Low-background experiment to search for double beta decay of 106Cd using 106CdWO4 scintillator

P. Belli1,2, R. Bernabei1,2,*, F. Cappella3,4, V. Caracciolo1,2, R. Cerulli1,2, F. A. Danevich2,5, A. Inchicchitti3,4, D. V. Kasperovych5, V. R. Klavdiienko5, V. V. Kobychev5, A. Leoncini1,2, V. Merlo1,2, O. G. Polischuk3,5, V. I. Tretyak5,6

1 Department of Physics, University of Rome "Tor Vergata", Rome, Italy
2 National Institute for Nuclear Physics, Rome Section Tor Vergata, Rome, Italy
3 National Institute for Nuclear Physics, Rome Section, Rome, Italy
4 Department of Physics, University of Rome "La Sapienza", Rome, Italy
5 Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine
6 National Institute for Nuclear Physics, Gran Sasso National Laboratory, Assergi, Italy

*Corresponding author. E-mail address:

Abstract: An experiment to search for 2ε-, εβ+- and 2β+-decays of 106Cd, using a 215 g cadmium tungstate scintillation crystal enriched at 66 % by 106Cd (106CdWO4) is carried out at the Gran Sasso underground laboratory (Italy). Events in the 106CdWO4 detector are recorded in (anti)coincidences with two large-volume CdWO4 scintillation counters. The design of the detector system, calibration and background measurements, methods, and results of data analysis to determine key detector characteristics are described. The experimental data are compared with Monte Carlo simulation results, and a background model is constructed. The radioactive contamination of the setup components is studied. The sensitivity of the experiment approaches the level of theoretical predictions for the 2νεβ+-decay channel, while for other possible 2β-decay channels it is already on the level of lim T1/2 ∼ 1021-1022 years.

Keywords: 106Cd, double beta decay, 2ε, εβ+, 2β+, low background, scintillation detector.


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