Lowering the CUORE energy threshold

S Copello,E Ferri,Y Mei,C Gotti,K M Heeger,F Terranova,C Tomei,H Z Huang,M Maino,F Orio,S Dell’Oro,C Bucci,K E Lim,L Taffarello,M Faverzani,N Casali,O Cremonesi,H W Wang,C Rusconi,L Gironi,V Pettinacci,P Carniti,E B Norman,M Pallavicini,M Sisti,N Chott,E E Haller,D Chiesa,B S Wang,B X Zhu,L Canonica,T Wise,V Palmieri,F Bellini,Y G ,A Franceschi ,A D'addabbo ,John E Wilson ,R Hennings‐Yeomans ,C Pagliarone ,J W Beeman ,Alan Р Smith ,R Maruyama ,Thomas Banks ,E V Hansen ,C Pira ,R.w Kadel ,P Mosteiro ,Stephen Trentalange ,A Camacho,F T Avignone,M Pavan,L Pattavina,T D Gutierrez,M Vignati,Yu G Kolomensky,G Q Zhang,D Santone,D Q Fang,P Gorla,C Rosenfeld,K Han,S Pozzi,G Pessina,S L Wagaarachchi,A Drobizhev,L Marini,I Dafinei,E Previtali,L A Winslow,D R Artusa,M M Deninno,A Branca,J L Ouellet,M Biassoni,M Martinez,T Napolitano,V Singh,S Morganti,S Pirro,E Fiorini,C Brofferio,K P Hickerson,L Cappelli,A Giuliani,L Gladstone,S Capelli,S Sangiorgio,N D Scielzo,X G Cao,C Alduino,C J Davis,M Tenconi,C Cosmelli,A Woodcraft,M L Di Vacri,S Zimmermann,S Di Domizio,L Cassina,A Giachero,N Moggi,A Nucciotti,A Caminata,C Ligi,K Alfonso,R J Creswick,T O’Donnell,F Ferroni,S J Freedman,L Carbone,J S Cushman,A Bersani,G Fernandes,B K Fujikawa,G Bari,X Liu,L Cardani,C Nones,L Zanotti,A Leder,G Piperno,O Azzolini,M Clemenza,G Keppel,S Zucchelli

doi:10.1088/1742-6596/888/1/012047

Abstract

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale double beta decay experiment based on TeO2 cryogenic bolometers and is currently in the last construction stage at the Gran Sasso National Laboratory (LNGS). Its primary goal is to observe neutrino-less double beta decay of 130Te, however thanks to the ultra-low background and large projected exposure it could also be suitable for other rare event searches, as the detection of solar axions, neutrinos from type II supernovae or direct detection of dark matter. The sensitivity for these searches will depend on the performance achieved at the low energy threshold. For this reason a trigger algorithm based on continuous data filtering has been developed which will allow lowering the threshold down to the few keV region. The new trigger has been tested in CUORE-0, a single-tower CUORE prototype consisting of 52 TeO2 bolometers and recently concluded, and here we present the results in terms of trigger efficiency, data selection and low-energy calibration.

Highlights

H s∗(ωk) e−jωkiM N where s(ωk) is the Discrete Fourier Transform (DFT) of the average discrete pulse shape si, iM is the position of the maximum of si, and h is a normalization constant that leaves unmodified the amplitude of the signal
Cryogenic Underground Observatory for Rare Events (CUORE)-0 results CUORE-0 ran for about two years and we used its data to test the optimum trigger in terms of trigger efficiency, data selection and energy calibration
Trigger efficiency can be evaluated in two ways

Summary

Introduction

Si is obtained averaging different pulse shapes while N (ωk) is made by averaging the power spectrum of a large set of data windows not containing signals. The filtered baseline is analyzed with a simple threshold trigger: when the samples exceed a certain value, the trigger fires. An exception is made since the filtered pulse presents lobes at both sides and, if the pulse energy is high enough, they can exceed the threshold and produce fake signals.

Results

Conclusion