Improved measurement of $^8$B solar neutrinos with 1.5 kt y of Borexino exposure
Creators: name: The Borexino Collaboration
name: Agostini, M.
name: Altenmüller, K.
name: Appel, S.
name: Atroshchenko, V.
name: Bagdasarian, Z.
name: Basilico, D.
name: Bellini, G.
name: Benziger, J.
name: Bick, D.
name: Bravo, D.
name: Caccianiga, B.
name: Calaprice, F.
name: Caminata, A.
name: Cavalcante, P.
name: Chepurnov, A.
name: D'Angelo, D.
name: Davini, S.
name: Derbin, A.
name: Di Giacinto, A.
name: Di Marcello, V.
name: Ding, X. F.
name: Di Ludovico, A.
name: Di Noto, L.
name: Drachnev, I.
name: Formozov, A.
name: Franco, D.
name: Galbiati, C.
name: Gschwender, M.
name: Ghiano, C.
name: Giammarchi, M.
name: Gromov, A. Goretti M.
name: Guffanti, D.
name: Hagner, C.
name: Houdy, T.
name: Hungerford, E.
name: Ianni, Aldo
name: Ianni, Andrea
name: Jany, A.
name: Jeschke, D.
name: Kobychev, V.
name: Korga, G.
name: Kumaran, S.
name: Lachenmaier, T.
name: Laubenstein, M.
name: Litvinovich, E.
name: Lombardi, P.
name: Lomskaya, I.
name: Ludhova, L.
name: Lukyanchenko, G.
name: Lukyanchenko, L.
name: Machulin, I.
name: Marcocci, S.
name: Martyn, J.
name: Meroni, E.
name: Meyer, M.
name: Miramonti, L.
name: Misiaszek, M.
name: Muratova, V.
name: Neumair, B.
name: Nieslony, M.
name: Nugmanov, R.
name: Oberauer, L.
name: Orekhov, V.
name: Ortica, F.
name: Pallavicini, M.
name: Papp, L.
name: Penek, Ö.
name: Pietrofaccia, L.
name: Pilipenko, N.
name: Pocar, A.
name: Raikov, G.
name: Ranalli, M. T.
name: Ranucci, G.
name: Razeto, A.
name: Re, A.
name: Redchuk, M.
name: Romani, A.
name: Rossi, N.
name: Rottenanger, S.
name: Schönert, S.
name: Semenov, D.
name: Skorokhvatov, M.
name: Smirnov, O.
name: Sotnikov, A.
name: Suvorov, Y.
name: Tartaglia, R.
name: Testera, G.
name: Thurn, J.
name: Unzhakov, E.
name: Vishneva, A.
name: Vogelaar, R. B.
name: von Feilitzsch, F.
name: Wojcik, M.
name: Wurm, M.
name: Zavatarelli, S.
name: Zuber, K.
name: Zuzel, G.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We report on an improved measurement of the $^8$B solar neutrino interaction rate with the Borexino experiment at the Laboratori Nazionali del Gran Sasso. Neutrinos are detected via their elastic scattering on electrons in a large volume of liquid scintillator. The measured rate of scattered electrons above 3 MeV of energy is $0.223\substack{+0.015 \\ -0.016}\,(stat)\,\substack{+0.006 \\ -0.006}\,(syst)$ cpd/100 t, which corresponds to an observed solar neutrino flux assuming no neutrino flavor conversion of $Φ\substack{\rm ES \\ ^8\rm B}=2.57\substack{+0.17 \\ -0.18}(stat)\substack{+0.07\\ -0.07}(syst)\times$10$^6$ cm$^{-2}\,$s$^{-1}$. This measurement exploits the active volume of the detector in almost its entirety for the first time, and takes advantage of a reduced radioactive background following the 2011 scintillator purification campaign and of novel analysis tools providing a more precise modeling of the background. Additionally, we set a new limit on the interaction rate of solar $hep$ neutrinos, searched via their elastic scattering on electrons as well as their neutral current-mediated inelastic scattering on carbon, $^{12}$C($ν,ν'$)$^{12}$C* ($E_γ$= 15.1 MeV).
description: 14 pages, 13 figures, 4 tables