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Register a new userStudy of systematic effects in beta decay measurements with AgReO4 calorimeters
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Added by
Alessandro Monfardini
Publication date
2005
fields
Physics
and research's language is
English
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AgReO4 microcalorimeters are planned to be used again in the next generation of calorimetric neutrino mass experiments with sensitivity down to 0.2 eV. The understanding and characterization of all possible sources of systematic uncertainties is crucial. In this work we focus on two of these sources, which have been studied in the 10 detectors of the Milano AgReO4 array experiment (MIBETA): a) the solid-state Beta Environmental Fine Structure (BEFS) observed for the first time in AgReO4; b) the detector energy response for internal beta events, which has been investigated with a dedicated measurement using a 44Ti gamma source. The possible effects on neutrino mass experiments due to the incomplete understanding of these two aspects are discussed.
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The suppression of spurious events in the region of interest for neutrinoless double beta decay will play a major role in next generation experiments. The background of detectors based on the technology of cryogenic calorimeters is expected to be dominated by {alpha} particles, that could be disentangled from double beta decay signals by exploiting the difference in the emission of the scintillation light. CUPID-0, an array of enriched Zn$^{82}$Se scintillating calorimeters, is the first large mass demonstrator of this technology. The detector started data-taking in 2017 at the Laboratori Nazionali del Gran Sasso with the aim of proving that dual read-out of light and heat allows for an efficient suppression of the {alpha} background. In this paper we describe the software tools we developed for the analysis of scintillating calorimeters and we demonstrate that this technology allows to reach an unprecedented background for cryogenic calorimeters.
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