Pulse shape discrimination in CUPID-Mo using principal component analysis

• Published in: Journal of instrumentation 2021-03, Vol.16 (3), p.P03032
• Main Authors: Huang, R., Armengaud, E., Augier, C., Barabash, A.S., Bellini, F., Benato, G., Benoît, A., Beretta, M., Bergé, L., Billard, J., Borovlev, Yu. A., Bourgeois, Ch, Brudanin, V.B., Camus, P., Cardani, L., Casali, N., Cazes, A., Chapellier, M., Charlieux, F., de Combarieu, M., Dafinei, I., Danevich, F.A., De Jesus, M., Dixon, T., Dumoulin, L., Eitel, K., Ferri, F., Fujikawa, B.K., Gascon, J., Gironi, L., Giuliani, A., Grigorieva, V.D., Gros, M., Guerard, E., Helis, D.L., Huang, H.Z., Johnston, J., Juillard, A., Khalife, H., Kleifges, M., Kobychev, V.V., Kolomensky, Yu. G., Konovalov, S.I., Loaiza, P., Ma, L., Makarov, E.P., de Marcillac, P., Mariam, R., Marini, L., Marnieros, S., Misiak, D., Navick, X.-F., Nones, C., Norman, E.B., Olivieri, E., Ouellet, J.L., Pagnanini, L., Pari, P., Pattavina, L., Paul, B., Pavan, M., Peng, H., Pessina, G., Pirro, S., Poda, D.V., Polischuk, O.G., Previtali, E., Redon, Th, Rozov, S., Rusconi, C., Sanglard, V., Scarpaci, J.A., Schäffner, K., Schmidt, B., Shen, Y., Shlegel, V.N., Siebenborn, B., Singh, V., Tomei, C., Tretyak, V.I., Umatov, V.I., Vagneron, L., Velázquez, M., Weber, M., Welliver, B., Winslow, L., Xue, M., Yakushev, E., Zarytskyy, M.M., Zolotarova, A.S.
• Format: Article
• Language: English
• Subjects: Beta decay; Bolometers; Data Analysis, Statistics and Probability; Instrumentation and Detectors; Nuclear Experiment; OTHER INSTRUMENTATION; Physics; Principal components analysis; Pulse shape; Sensors
• ISSN: 1748-0221; 1748-0221
• DOI: 10.1088/1748-0221/16/03/P03032

CUPID-Mo is a cryogenic detector array designed to search for neutrinoless double-beta decay (0νββ) of 100 Mo. It uses 20 scintillating 100 Mo-enriched Li 2 MoO 4 bolometers instrumented with Ge light detectors to perform active suppression of α backgrounds, drastically reducing the expected background in the 0νββ signal region. As a result, pileup events and small detector instabilities that mimic normal signals become non-negligible potential backgrounds. These types of events can in principle be eliminated based on their signal shapes, which are different from those of regular bolometric pulses. We show that a purely data-driven principal component analysis based approach is able to filter out these anomalous events, without the aid of detector response simulations.