7Be Solar Neutrino Measurement with KamLAND

• Published in: arXiv.org 2015-10
• Main Authors: Gando, A, Gando, Y, Hanakago, H, Ikeda, H, Inoue, K, Ishidoshiro, K, Ishikawa, H, Kishimoto, Y, Koga, M, Matsuda, R, Matsuda, S, Mitsui, T, Motoki, D, Nakajima, K, Nakamura, K, Obata, A, Oki, A, Oki, Y, Otani, M, Shimizu, I, Shirai, J, Suzuki, A, Tamae, K, Ueshima, K, Watanabe, H, Xu, B D, Yamada, S, Yamauchi, Y, Yoshida, H, Kozlov, A, Takemoto, Y, Yoshida, S, Grant, C, Keefer, G, McKee, D W, Piepke, A, Banks, T I, Bloxham, T, Freedman, S J, Fujikawa, B K, Han, K, Hsu, L, Ichimura, K, Murayama, H, O'Donnell, T, Steiner, H M, Winslow, L A, Dwyer, D, Mauger, C, McKeown, R D, Zhang, C, Berger, B E, Lane, C E, Maricic, J, Miletic, T, Learned, J G, Sakai, M, Horton-Smith, G A, Tang, A, Downum, K E, Tolich, K, Efremenko, Y, Kamyshkov, Y, Perevozchikov, O, Karwowski, H J, Markoff, D M, Tornow, W, Detwiler, J A, Enomoto, S, Heeger, K, Decowski, M P, The KamLAND Collaboration
• Format: Article
• Language: English
• Subjects: Elastic scattering; Flavors; Flux; Mathematical models; Neutrinos; Solar neutrinos; Solar oscillations
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1405.6190

We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7Be solar neutrinos based on a 165.4 kton-day exposure of KamLAND. The observed rate is 582 +/- 90 (kton-day)^-1, which corresponds to a 862 keV 7Be solar neutrino flux of (3.26 +/- 0.50) x 10^9 cm^-2s^-1, assuming a pure electron flavor flux. Comparing this flux with the standard solar model prediction and further assuming three flavor mixing, a nu_e survival probability of 0.66 +/- 0.14 is determined from the KamLAND data. Utilizing a global three flavor oscillation analysis, we obtain a total 7Be solar neutrino flux of (5.82 +/- 0.98) x 10^9 cm^-2s^-1, which is consistent with the standard solar model predictions.