PoS - Proceedings of Science
Volume 441 - XVIII International Conference on Topics in Astroparticle and Underground Physics (TAUP2023) - Dark Matter and its Detection
Confirmation of the excess of ionization events in DAMIC at SNOLAB with skipper CCDs
M. Traina*,  DAMIC, DAMIC-M and SENSEI, A. Aguilar-Arevalo, I. Arnquist, N. Avalos, L. Barak, D. Baxter, X. Bertou, I.M. Bloch, A.M. Botti, M. Cababie, G. Cancelo, N. Castello-Mor, B.A. Cervantes-Vergara, A.E. Chavarria, J. Cortabitarte-Gutiérrez, M. Crisler, J. Cuevas-Zepeda, A. Dastgheibi-Fard, C. De Dominicis, O. Deligny, A. Drlica-Wagner, J. Duarte-Campderros, J.C. D'Olivo, R. Essig, E. Estrada, J. Estrada, E. Etzion, F. Favela-Perez, N. Gadola, R. Gaior, S.E. Holland, T. Hossbach, L. Iddir, B. Kilminster, Y. Korn, A. Lantero-Barreda, I.T. Lawson, S.C. Lee, A. Letessier-Selvon, P. Loaiza, A. Lopez-Virto, S. Luoma, E. Marrufo-Villalpando, K.J. McGuire, G.F. Moroni, S. Munagavalasa, D. Norcini, A. Orly, G. Papadopoulos, S. Paul, S.E. Perez, A. Piers, P. Privitera, P. Robmann, D. Rodrigues, N.A. Saffold, S. Scorza, M. Settimo, A. Singal, R. Smida, M. Sofo-Haro, L. Stefanazzi, K. Stifter, J. Tiffenberg, M. Traina, S. Uemura, I. Vila, R. Vilar, T. Volansky, G. Warot, R. Yajur, T.T. Yu and J.P. Zopounidiset al. (click to show)
Full text: pdf
Pre-published on: February 20, 2024
Published on: March 22, 2024
We present results from a 3.2 kg-day target exposure of two 24-megapixel skipper charge-coupled devices (CCDs) deployed in the DAMIC setup at SNOLAB. With a $10\times$ reduction in pixel noise, we investigate the excess population of low-energy bulk events previously observed above expected backgrounds. We address the dominant systematic uncertainty of the previous analysis through a depth fiducialization designed to reject surface backgrounds on the CCDs. The observed energy spectrum and spatial distribution of ionization events with electron-equivalent energies ${<}500$ eV confirm the presence of a bulk excess compatible with previous findings. This measurement establishes the existence of a prominent source of low-energy events in the CCD target with characteristic rate of ${\sim}7$ events per kg-day, and energies ${\sim}80$ eV, whose origin remains unknown.
DOI: https://doi.org/10.22323/1.441.0059
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.