Constraints on Sub-GeV Dark-Matter-Electron Scattering from the DarkSide-50 Experiment

Agnes, P; Ifm, Albuquerque; Alexander, T; Alton, Ak; Araujo, Gr; Asner, Dm; Ave, M; Back, Ho; Baldin, B; Batignani, G; Biery, K; Bocci, V; Bonfini, G; Bonivento, W; Bottino, B; Budano, F; Bussino, S; Cadeddu, M; Cadoni, M; Calaprice, F; Caminata, A; Canci, N; Candela, A; Caravati, M; Cariello, M; Carlini, M; Carpinelli, M; Catalanotti, S; Cataudella, V; Cavalcante, P; Cavuoti, S; Cereseto, R; Chepurnov, A; Cicalo, C; Cifarelli, L; Cocco, Ag; Covone, G; D'Angelo, D; D'Incecco, M; D'Urso, D; Davini, S; De Candia, A; De Cecco, S; De Deo, M; De Filippis, G; De Rosa, G; De Vincenzi, M; Demontis, P; Derbin, Av; Devoto, A; Di Eusanio, F; Di Pietro, G; Dionisi, C; Downing, M; Edkins, E; Empl, A; Fan, A; Fiorillo, G; Fomenko, K; Franco, D; Gabriele, F; Gabrieli, A; Galbiati, C; Abia, Pg; Ghiano, C; Giagu, S; Giganti, C; Giovanetti, Gk; Gorchakov, O; Goretti, Am; Granato, F; Gromov, M; Guan, M; Guardincerri, Y; Gulino, M; Hackett, Br; Hassanshahi, Mh; Herner, K; Hosseini, B; Hughes, D; Humble, P; Hungerford, Ev; Ianni, A; Ianni, A; Ippolito, V; James, I; Johnson, Tn; Kahn, Y; Keeter, K; Kendziora, Cl; Kochanek, I; Koh, G; Korablev, D; Korga, G; Kubankin, A; Kuss, M; La Commara, M; Lai, M; X, Li; Lisanti, M; Lissia, M; Loer, B; Longo, G; Y, Ma; Machado, Aa; Machulin, In; Mandarano, A; Mapelli, L; Mari, Sm; Maricic, J; Martoff, Cj; Messina, A; Meyers, Pd; Milincic, R; Mishra-Sharma, S; Monte, A; Morrocchi, M; Mount, Bj; Muratova, Vn; Musico, P; Nania, R; Agasson, An; Nozdrina, Ao; Oleinik, A; Orsini, M; Ortica, F; Pagani, L; Pallavicini, M; Pandola, L; Pantic, E; Paoloni, E; Pazzona, F; Pelczar, K; Pelliccia, N; Pesudo, V; Picciau, E; Pocar, A; Pordes, S; Poudel, Ss; Pugachev, Da; Qian, H; Ragusa, F; Razeti, M; Razeto, A; Reinhold, B; Renshaw, Al; Rescigno, M; Riffard, Q; Romani, A; Rossi, B; Rossi, N; Sablone, D; Samoylov, O; Sands, W; Sanfilippo, S; Sant, M; Santorelli, R; Savarese, C; Scapparone, E; Schlitzer, B; Segreto, E; Semenov, Da; Shchagin, A; Sheshukov, A; Singh, Pn; Skorokhvatov, Md; Smirnov, O; Sotnikov, A; Stanford, C; Stracka, S; Suffritti, Gb; Suvorov, Y; Tartaglia, R; Testera, G; Tonazzo, A; Trinchese, P; Unzhakov, Ev; Verducci, M; Vishneva, A; Vogelaar, B; Wada, M; Waldrop, Tj; Wang, H; Wang, Y; Watson, Aw; Westerdale, S; Wojcik, Mm; Wojcik, M; Xiang, X; Xiao, X; Yang, C; Z, Ye; Zhu, C; Zichichi, A; Zuzel, G

doi:10.1103/PhysRevLett.121.111303

We present new constraints on sub-GeV dark-matter particles scattering off electrons based on 6780.0 kg d of data collected with the DarkSide-50 dual-phase argon time projection chamber. This analysis uses electroluminescence signals due to ionized electrons extracted from the liquid argon target. The detector has a very high trigger probability for these signals, allowing for an analysis threshold of three extracted electrons, or approximately 0.05 keVee. We calculate the expected recoil spectra for dark matterelectron scattering in argon and, under the assumption of momentum-independent scattering, improve upon existing limits from XENON10 for dark-matter particles with masses between 30 and 100 MeV/c(2).