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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N. D. Khanbekov¹, V. V. Alenkov², A. A. Burenkov¹, O. A. Buzanov², V. N. Kornoukhov<sup>1

1</sup>Institute for Theoretical and Experimental Physics, Moscow, Russia
²JSC Fomos-Materials, Moscow, Russia

Abstract: The sensitivity of neutrinoless double beta (0ν2β) decay experiments is mainly dependent on the internal background of a detector which, in its turn, is defined by the purity of material and possibility for selection of background events. The AMoRE (Advanced Mo based Rare process Experiment) collaboration plans to use ⁴⁰Ca¹⁰⁰MoO₄ scintillation crystals as a detector for search of 0ν2β decay of ¹⁰⁰Mo isotope. A purpose of this paper is further investigation of internal background of ⁴⁰Ca¹⁰⁰MoO₄ scintillation elements with a low background setup at YangYang underground laboratory. We present new approaches for selection of background events from analyzing data and the latest updated values of background index of ⁴⁰Ca¹⁰⁰MoO₄ crystals as a result of the new technique application.

Keywords: neutrinoless double beta decay, data analysis, scintillators, calcium molybdate, low-background physics, time-amplitude analysis, radioactive background.

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