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   Periodicity: 4 times per year   Open access peer reviewed journal

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P. Belli¹, R. Bernabei^1,2, R. S. Boiko³, V. B. Brudanin⁴, F. Cappella^5,6, V. Caracciolo⁷, R. Cerulli⁷, D. M. Chernyak³, F. A. Danevich³, S. d'Angelo^1,2, A. E. Dossovitskiy⁸, E. N. Galashov⁹, A. Incicchitti^5,6, V. V. Kobychev³, S. S. Nagorny³, F. Nozzoli¹, B. N. Kropivyansky³, V. M. Kudovbenko³, A. L. Mikhlin⁸, A. S. Nikolaiko³, D. V. Poda^3,7, R. B. Podviyanuk³, O. G. Polischuk³, D. Prosperi^5,6, V. N. Shlegel⁹, Yu. G. Stenin⁹, J. Suhonen¹⁰, V. I. Tretyak³, Ya. V. Vasiliev<sup>9

1</sup>Istituto Nazionale di Fisica Nucleare, Sezione Roma "Tor Vergata", Rome, Italy
²Dipartimento di Fisica, Università di Roma "Tor Vergata", Rome, Italy
³Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine
⁴Joint Institute for Nuclear Research, Dubna, Moscow region, Russia
⁵Istituto Nazionale di Fisica Nucleare, Sezione Roma "La Sapienza", Rome, Italy
⁶Dipartimento di Fisica, Università di Roma "La Sapienza", Rome, Italy
⁷Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso, Assergi (AQ), Italy
⁸Joint Stock Company NeoChem, Moscow, Russia
⁹Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia
¹⁰Department of Physics, University of Jyväskylä, Jyväskylä, Finland

Abstract: An experiment to search for 2β processes in ¹⁰⁶Cd with the help of ¹⁰⁶CdWO₄ crystal scintillator (mass of 215 g), enriched in ¹⁰⁶Cd up to 66%, is in progress at the Gran Sasso National Laboratories of the INFN (Italy). After 1320 h of data taking, limits on double beta processes in ¹⁰⁶Cd have been established on the level of 10¹⁹ - 10²⁰ yr, in particular (all the results at 90% C.L.): T_1/2(0ν2ε) > 3.6 · 10²⁰ yr, T_1/2(2νεβ⁺) > 7.2 · 10¹⁹ yr, and T_1/2(2ν2β⁺) > 2.5 · 10²⁰ yr. Resonant 0ν2ε processes have been restricted as T_1/2(0ν2K) > 1.4 · 10²⁰ yr and T_1/2(0νLK) > 3.2 · 10²⁰ yr. A possible resonant enhancement of the 0ν2ε processes is estimated in the framework of the QRPA approach.

Keywords: double beta decay, ¹⁰⁶Cd, ¹⁰⁶CdWO₄ crystal scintillator.

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