ZnMoO4: A promising bolometer for neutrinoless double beta decay searches

Abstract

a b s t r a c tWe investigate the performances of two ZnMoO 4 scintillating crystals operated as bolometers, in view of a next generation experiment to search the neutrinoless double beta decay of 100 Mo. We present the results of the a vs b/c discrimination, obtained through the scintillation light as well as through the study of the shape of the thermal signal alone. The separation obtained at the 2615 keV line of 208 Tl is 8r, using the heat-light scatter plot, while it exceeds 20r using the shape of the thermal pulse alone. The achieved FWHM energy resolution ranges from 2.4 keV (at 238 keV) to 5.7 keV (at 2615 keV). The internal radioactive contaminations of the ZnMoO 4 crystals were evaluated through a 407 h background measurement.The obtained limit is <32 lBq/kg for 228 Th and 226 Ra. These values were used for a Monte Carlo simulation aimed at evaluating the achievable background level of a possible, future array of enriched Zn 100 MoO 4 crystals.

Present and future strategies for Neutrinoless Double Beta decay searches

“…Beautiful results have been obtained so far with scintillating bolometers [21][22][23][24][25][26] which could allow to study in the future new 0νDBD active isotopes with improved sensitivity. LUCIFER [27] will consist in an array of scintillating bolometers operated at 10-20 mK.…”

“…The proof of principle with ∼10 kg of enriched Se, embedded in ZnSe scintillating crystals is foreseen in 2015. Another very promising compound that will be investigated is ZnMoO 4 [23][24][25][26]. LUCIFER is in the R&D phase, and can be considered as a demonstrator for a possible upgrade of CUORE, with however a considerable sensitivity by itself.…”

Rietveld refinements, impedance spectroscopy and phase transition of the polycrystalline ZnMoO4 ceramics

“…In the last years, zinc molybdate ZnMoO 4 was investigated for its luminescence properties [7][8][9][10], for applications in bolometers, scintillation detectors [11][12][13][14][15], humidity sensors [16], photocatalysis [17][18][19], microwave dielectric devices [20] and battery electrodes [21].However, this material presents different structures depending on the elaboration conditions. Traditionally two phases α-ZnMoO 4 and β-ZnMoO 4 , with triclinic and monoclinic structures respectively, have been synthesized by different techniques, such as hydrothermal method [22,18,23], solid state reaction [24][25][26][27][28][29], citrate complex precursors [30], co-precipitation method [31][32][33], electrospinning calcination method [34] and electrochemistry assisted ablation laser method [35].…”

Neutrinoless double-beta decay search with CUORE and CUORE-0 experiments

“…To distinguish signal electrons from α background, light emission can be used, either from Cherenkov radiation [22,23] or scintillation light [24,25,28,29], where the auxiliary light detector is usually another bolometer facing the main one. Recently new studies on scintillating bolometers showed the possibility to distinguish α from β/γ particles without light readout thanks to a different time-dependent shape of the heat signal [30,31]. Alternative methods based on the identification of surface interactions have also been devised (see, e.g.…”