The background model of the CUPID-Mo experiment

C. Augier; A. S. Barabash; F. Bellini; G. Benato; M. Beretta; L. Bergé; J. Billard; Yu. A. Borovlev; L. Cardani; N. Casali; A. Cazes; E. Celi; M. Chapellier; D. Chiesa; I. Dafinei; F. A. Danevich; M. De Jesus; P. de Marcillac; T. Dixon; L. Dumoulin; K. Eitel; F. Ferri; B. K. Fujikawa; J. Gascon; L. Gironi; A. Giuliani; V. D. Grigorieva; M. Gros; D. L. Helis; H. Z. Huang; R. Huang; L. Imbert; J. Johnston; A. Juillard; H. Khalife; M. Kleifges; V. V. Kobychev; Yu. G. Kolomensky; S. I. Konovalov; J. Kotila; P. Loaiza; L. Ma; E. P. Makarov; R. Mariam; L. Marini; S. Marnieros; X.-F. Navick; C. Nones; E. B. Norman; E. Olivieri; J. L. Ouellet; L. Pagnanini; L. Pattavina; B. Paul; M. Pavan; H. Peng; G. Pessina; S. Pirro; D. V. Poda; O. G. Polischuk; S. Pozzi; E. Previtali; Th. Redon; A. Rojas; S. Rozov; V. Sanglard; J. A. Scarpaci; B. Schmidt; Y. Shen; V. N. Shlegel; V. Singh; C. Tomei; V. I. Tretyak; V. I. Umatov; L. Vagneron; M. Velázquez; B. Welliver; L. Winslow; M. Xue; E. Yakushev; M. Zarytskyy; A. S. Zolotarova

doi:10.1140/epjc/s10052-023-11830-2

2023 Impact factor 4.2

Particles and Fields

Open Access

Eur. Phys. J. C (2023) 83: 675
https://doi.org/10.1140/epjc/s10052-023-11830-2

Regular Article - Experimental Physics

The background model of the CUPID-Mo $0 ν β β$ $0\nu \beta \beta$ experiment

C. Augier¹, A. S. Barabash², F. Bellini³^,4, G. Benato⁵^,6, M. Beretta⁷, L. Bergé⁸, J. Billard¹, Yu. A. Borovlev⁹, L. Cardani⁴, N. Casali⁴, A. Cazes¹, E. Celi⁵^,6, M. Chapellier⁸, D. Chiesa¹⁰^,11, I. Dafinei⁴, F. A. Danevich⁴^,12, M. De Jesus¹, P. de Marcillac⁸, T. Dixon⁸, L. Dumoulin⁸, K. Eitel¹³, F. Ferri¹⁵, B. K. Fujikawa¹⁴, J. Gascon¹, L. Gironi¹⁰^,11, A. Giuliani⁸, V. D. Grigorieva⁹, M. Gros¹⁵, D. L. Helis⁵^,6, H. Z. Huang¹⁶, R. Huang⁷, L. Imbert⁸^aj, J. Johnston¹⁷, A. Juillard¹, H. Khalife¹⁵, M. Kleifges¹⁸, V. V. Kobychev¹², Yu. G. Kolomensky⁷^,14, S. I. Konovalov², J. Kotila¹⁹^,20^,21, P. Loaiza⁸, L. Ma¹⁶, E. P. Makarov⁹, R. Mariam⁸, L. Marini⁵^,7, S. Marnieros⁸, X.-F. Navick¹⁵, C. Nones¹⁵, E. B. Norman²², E. Olivieri⁸, J. L. Ouellet¹⁷, L. Pagnanini⁵^,6, L. Pattavina⁶^,23, B. Paul¹⁵, M. Pavan¹⁰^,11, H. Peng²⁴, G. Pessina¹¹, S. Pirro⁶, D. V. Poda⁸, O. G. Polischuk⁴^,12, S. Pozzi¹¹, E. Previtali¹⁰^,11, Th. Redon⁸, A. Rojas²⁵, S. Rozov²⁶, V. Sanglard¹, J. A. Scarpaci⁸, B. Schmidt¹⁵, Y. Shen¹⁶, V. N. Shlegel⁹, V. Singh⁷, C. Tomei⁴, V. I. Tretyak⁶^,12, V. I. Umatov², L. Vagneron¹, M. Velázquez²⁷, B. Welliver⁷, L. Winslow¹⁷, M. Xue²⁴, E. Yakushev²⁶, M. Zarytskyy¹² and A. S. Zolotarova¹⁵

¹ Université Lyon 1, CNRS/IN2P3, IP2I-Lyon, 69622, Villeurbanne, France
² National Research Centre Kurchatov Institute, Kurchatov Complex of Theoretical and Experimental Physics, 117218, Moscow, Russia
³ Dipartimento di Fisica, Sapienza Università di Roma, P.le Aldo Moro 2, 00185, Rome, Italy
⁴ INFN, Sezione di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133, Rome, Italy
⁵ Gran Sasso Science Institute, 67100, L’Aquila, Italy
⁶ INFN, Laboratori Nazionali del Gran Sasso, 67100, Assergi, AQ, Italy
⁷ Department of Physics, University of California, 94720, Berkeley, CA, USA
⁸ Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405, Orsay, France
⁹ Nikolaev Institute of Inorganic Chemistry, 630090, Novosibirsk, Russia
¹⁰ Dipartimento di Fisica, Università di Milano-Bicocca, 20126, Milan, Italy
¹¹ INFN, Sezione di Milano-Bicocca, 20126, Milan, Italy
¹² Institute for Nuclear Research of NASU, 03028, Kyiv, Ukraine
¹³ Institute for Astroparticle Physics, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
¹⁴ Nuclear Science Division, Lawrence Berkeley National Laboratory, 94720, Berkeley, CA, USA
¹⁵ IRFU, CEA, Université Paris-Saclay, 91191, Gif-sur-Yvette, France
¹⁶ Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Fudan University, 200433, Shanghai, People’s Republic of China
¹⁷ Massachusetts Institute of Technology, 02139, Cambridge, MA, USA
¹⁸ Institute for Data Processing and Electronics, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
¹⁹ Department of Physics, University of Jyväskylä, PO Box 35, 40014, Jyvaskyla, Finland
²⁰ Finnish Institute for Educational Research, University of Jyväskylä, P.O. Box 35, 40014, Jyvaskyla, Finland
²¹ Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, 06520-8120, New Haven, CT, USA
²² Department of Nuclear Engineering, University of California, 94720, Berkeley, CA, USA
²³ Physik Department, Technische Universität München, 85748, Garching, Germany
²⁴ Department of Modern Physics, University of Science and Technology of China, 230027, Hefei, People’s Republic of China
²⁵ LSM, Laboratoire Souterrain de Modane, 73500, Modane, France
²⁶ Laboratory of Nuclear Problems, JINR, 141980, Dubna, Moscow Region, Russia
²⁷ Université Grenoble Alpes, CNRS, Grenoble INP, SIMAP, 38402, Saint Martin d’Héres, France

^aj leonard.imbert@ijclab.in2p3.fr

Received: 2 May 2023
Accepted: 10 July 2023
Published online: 28 July 2023

Abstract

CUPID-Mo, located in the Laboratoire Souterrain de Modane (France), was a demonstrator for the next generation $0 ν β β$ $0\nu \beta \beta$ decay experiment, CUPID. It consisted of an array of 20 enriched Li $_{2}$ $_{2}$ $^{100}$ $^{100}$ MoO $_{4}$ $$_4$$ bolometers and 20 Ge light detectors and has demonstrated that the technology of scintillating bolometers with particle identification capabilities is mature. Furthermore, CUPID-Mo can inform and validate the background prediction for CUPID. In this paper, we present a detailed model of the CUPID-Mo backgrounds. This model is able to describe well the features of the experimental data and enables studies of the $2 ν β β$ $2\nu \beta \beta$ decay and other processes with high precision. We also measure the radio-purity of the Li $_{2}$ $_{2}$ $^{100}$ $^{100}$ MoO $_{4}$ $$_4$$ crystals which are found to be sufficient for the CUPID goals. Finally, we also obtain a background index in the region of interest of 3.7 $_{- 0.8}^{+ 0.9}$ $^{+0.9}_{-0.8}$ (stat) $_{- 0.7}^{+ 1.5}$ $^{+1.5}_{-0.7}$ (syst) $\times 10^{- 3}$ $\times ~10 ^{-3}$ counts/ $Δ E_{FWHM} / {mol}_{iso} / year,$ $\Delta E_{\text {FWHM}}/\text {mol}_{\text {iso}}/\text {year},$ the lowest in a bolometric $0 ν β β$ $0\nu \beta \beta$ decay experiment.

© The Author(s) 2023

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.