First Indication of Solar 8-B Neutrinos via Coherent Elastic Neutrino-Nucleus Scattering with XENONnT

Aprile, E.; Aalbers, J.; Abe, K.; Ahmed Maouloud, S.; Althueser, L.; Andrieu, B.; Angelino, E.; Antón Martin, D.; Arneodo, F.; Baudis, L.; Bazyk, M.; Bellagamba, L.; Biondi, R.; Bismark, A.; Boese, K.; Brown, A.; Bruno, G.; Budnik, R.; Cai, C.; Capelli, C.; Cardoso, J.  m.  r.; Cimental Chávez, A.  p.; Colijn, A.  p.; Conrad, J.; Cuenca-García, J.  j.; D'Andrea, V.; Daniel Garcia, L.  c.; Decowski, M.  p.; Deisting, A.; Di Donato, C.; Di Gangi, P.; Diglio, S.; Eitel, K.; Elykov, A.; Ferella, A.  d.; Ferrari, C.; Fischer, H.; Flehmke, T.; Flierman, M.; Fulgione, W.; Fuselli, C.; Gaemers, P.; Gaior, R.; Galloway, M.; Gao, F.; Ghosh, S.; Giacomobono, R.; Glade-Beucke, R.; Grandi, L.; Grigat, J.; Guan, H.; Guida, M.; Gyorgy, P.; Hammann, R.; Higuera, A.; Hils, C.; Hoetzsch, L.; Hood, N.  f.; Iacovacci, M.; Itow, Y.; Jakob, J.; Joerg, F.; Kaminaga, Y.; Kara, M.; Kavrigin, P.; Kazama, S.; Kobayashi, M.; Koke, D.; Kopec, A.; Kuger, F.; Landsman, H.; Lang, R.  f.; Levinson, L.; Li, I.; Li, S.; Liang, S.; Lin, Y. -T.; Lindemann, S.; Lindner, M.; Liu, K.; Liu, M.; Loizeau, J.; Lombardi, F.; Long, J.; Lopes, J.  a.  m.; Luce, T.; Ma, Y.; Macolino, C.; Mahlstedt, J.; Mancuso, A.; Manenti, L.; Marignetti, F.; Marrodán Undagoitia, T.; Martens, K.; Masbou, J.; Masson, E.; Mastroianni, S.; Melchiorre, A.; Merz, J.; Messina, M.; Michael, A.; Miuchi, K.; Molinario, A.; Moriyama, S.; Morå, K.; Mosbacher, Y.; Murra, M.; Müller, J.; Ni, K.; Oberlack, U.; Paetsch, B.; Pan, Y.; Pellegrini, Q.; Peres, R.; Peters, C.; Pienaar, J.; Pierre, M.; Plante, G.; Pollmann, T.  r.; Principe, L.; Qi, J.; Qin, J.; Ramírez García, D.; Rajado, M.; Singh, R.; Sanchez, L.; Dos Santos, J.  m.  f.; Sarnoff, I.; Sartorelli, G.; Schreiner, J.; Schulte, P.; Schulze Eißing, H.; Schumann, M.; Scotto Lavina, L.; Selvi, M.; Semeria, F.; Shagin, P.; Shi, S.; Shi, J.; Silva, M.; Simgen, H.; Takeda, A.; Tan, P. -L.; Thers, D.; Toschi, F.; Trinchero, G.; Tunnell, C.  d.; Tönnies, F.; Valerius, K.; Vecchi, S.; Vetter, S.; Villazon Solar, F.  i.; Volta, G.; Weinheimer, C.; Weiss, M.; Wenz, D.; Wittweg, C.; V.  h.  s., Wu; Xing, Y.; Xu, D.; Xu, Z.; Yamashita, M.; Yang, L.; Ye, J.; Yuan, L.; Zavattini, G.; Zhong, M.; Null, Null

doi:10.1103/physrevlett.133.191002

We present the first measurement of nuclear recoils from solar B8 neutrinos via coherent elastic neutrino-nucleus scattering with the XENONnT dark matter experiment. The central detector of XENONnT is a low-background, two-phase time projection chamber with a 5.9 t sensitive liquid xenon target. A blind analysis with an exposure of 3.51 t×yr resulted in 37 observed events above 0.5 keV, with (26.4-1.3+1.4) events expected from backgrounds. The background-only hypothesis is rejected with a statistical significance of 2.73σ. The measured B8 solar neutrino flux of (4.7-2.3+3.6)×106 cm-2 s-1 is consistent with results from the Sudbury Neutrino Observatory. The measured neutrino flux-weighted CEνNS cross section on Xe of (1.1-0.5+0.8)×10-39 cm2 is consistent with the Standard Model prediction. This is the first direct measurement of nuclear recoils from solar neutrinos with a dark matter detector.