Eur. Phys. J. C (2015) 75: 12
https://doi.org/10.1140/epjc/s10052-014-3225-4

Letter

TeO bolometers with Cherenkov signal tagging: towards next-generation neutrinoless double-beta decay experiments

¹ INFN Laboratori Nazionali del Gran Sasso, 67010, Assergi (AQ), Italy
² Dipartimento di Scienze Fisiche e Chimiche, Università degli studi dell’Aquila, 67100, Coppito (AQ), Italy
³ Dipartimento di Fisica, Sapienza Università di Roma, 00185, Rome, Italy
⁴ INFN Sezione di Roma, P.le A. Moro 2, 00185, Rome, Italy
⁵ Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
⁶ INFN Sezione di Genova, 16146, Genoa, Italy
⁷ Dipartimento di Fisica, Università di Genova, 16146, Genoa, Italy
⁸ INFN Sezione di Milano Bicocca, 20126, Milan, Italy
⁹ Dipartimento di Fisica, Università di Milano Bicocca, 20126, Milan, Italy
¹⁰ INFN Gran Sasso Science Institute, 67100, L‘Aquila, Italy

^* e-mail: marco.vignati@roma1.infn.it

Received: 15 April 2014
Accepted: 11 December 2014
Published online: 14 January 2015

Abstract

CUORE, an array of 988 TeO bolometers, is about to be one of the most sensitive experiments searching for neutrinoless double-beta decay. Its sensitivity could be further improved by removing the background from radioactivity. A few years ago it was pointed out that the signal from s can be tagged by detecting the emitted Cherenkov light, which is not produced by s. In this paper we confirm this possibility. For the first time we measured the Cherenkov light emitted by a CUORE crystal, and found it to be 100 eV at the -value of the decay. To completely reject the background, we compute that one needs light detectors with baseline noise below 20 eV RMS, a value which is 3–4 times smaller than the average noise of the bolometric light detectors we are using. We point out that an improved light detector technology must be developed to obtain TeO bolometric experiments able to probe the inverted hierarchy of neutrino masses.