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

• Published in: The European physical journal. C, Particles and fields Vol. 83; no. 7
• Main Authors: Augier, C., Barabash, A. S., Bellini, F., Benato, G., Beretta, M., Bergé, L., Billard, J., Borovlev, Yu. A., Cardani, L., Casali, N., Cazes, A., Celi, E., Chapellier, M., Chiesa, D., Dafinei, I., Danevich, F. A., De Jesus, M., de Marcillac, P., Dixon, T., Dumoulin, L., Eitel, K., Ferri, F., Fujikawa, B. K., Gascon, J., Gironi, L., Giuliani, A., Grigorieva, V. D., Gros, M., Helis, D. L., Huang, H. Z., Huang, R., Imbert, L., Johnston, J., Juillard, A., Khalife, H., Kleifges, M., Kobychev, V. V., Kolomensky, Yu. G., Konovalov, S. I., Kotila, J., Loaiza, P., Ma, L., Makarov, E. P., Mariam, R., Marini, L., Marnieros, S., Navick, X.-F., Nones, C., Norman, E. B., Olivieri, E., Ouellet, J. L., Pagnanini, L., Pattavina, L., Paul, B., Pavan, M., Peng, H., Pessina, G., Pirro, S., Poda, D. V., Polischuk, O. G., Pozzi, S., Previtali, E., Redon, Th, Rojas, A., Rozov, S., Sanglard, V., Scarpaci, J. A., Schmidt, B., Shen, Y., Shlegel, V. N., Singh, V., Tomei, C., Tretyak, V. I., Umatov, V. I., Vagneron, L., Velázquez, M., Welliver, B., Winslow, L., Xue, M., Yakushev, E., Zarytskyy, M., Zolotarova, A. S.
• Format: Journal Article
• Language: English
• Published: United States Springer Nature 28.07.2023
• Subjects: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• ISSN: 1434-6052; 1434-6052
• DOI: 10.1140/epjc/s10052-023-11830-2

Abstract CUPID-Mo, located in the Laboratoire Souterrain de Modane (France), was a demonstrator for the next generation $$0\nu \beta \beta $$ 0 ν β β 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 $$2\nu \beta \beta $$ 2 ν β β 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  $$^{+0.9}_{-0.8}$$ - 0.8 + 0.9  (stat) $$^{+1.5}_{-0.7}$$ - 0.7 + 1.5  (syst)  $$\times ~10 ^{-3}$$ × 10 - 3  counts/ $$\Delta E_{\text {FWHM}}/\text {mol}_{\text {iso}}/\text {year},$$ Δ E FWHM / mol iso / year , the lowest in a bolometric $$0\nu \beta \beta $$ 0 ν β β decay experiment.