A Caltech Library Service

Precision measurement of neutrino oscillation parameters with KamLAND

Abe, S. and Ebihara, T. and Enomoto, S. and Furuno, K. and Gando, Y. and Ichimura, K. and Ikeda, H. and Inoue, K. and Kibe, Y. and Kishimoto, Y. and Koga, M. and Kozlov, A. and Minekawa, Y. and Mitsui, T. and Nakajima, K. and Nakajima, K. and Nakamura, K. and Nakamura, M. and Owada, K. and Shimizu, I. and Shimizu, Y. and Shirai, J. and Suekane, F. and Suzuki, A. and Takemoto, Y. and Tamae, K. and Terashima, A. and Watanabe, H. and Yonezawa, E. and Yoshida, S. and Busenitz, J. and Classen, T. and Grant, C. and Keefer, G. and Leonard, D. S. and McKee, D. and Piepke, A. and Decowski, M. P. and Detwiler, J. A. and Freedman, S. J. and Fujikawa, B. K. and Gray, F. and Guardincerri, E. and Hsu, L. and Kadel, R. and Lendvai, C. and Luk, K.-B. and Murayama, H. and O’Donnell, T. and Steiner, H. M. and Winslow, L. A. and Dwyer, D. A. and Jillings, C. and Mauger, C. and McKeown, R. D. and Vogel, P. and Zhang, Z. and Berger, B. E. and Lane, C. E. and Maricic, J. and Miletic, T. and Batygov, M. and Learned, J. G. and Matsuno, S. and Pakvasa, S. and Foster, J. and Horton-Smith, G. A. and Tang, A. and Dazeley, S. and Downum, K. E. and Gratta, G. and Tolich, K. and Bugg, W. and Efremenko, Y. and Kamyshkov, Y. and Perevozchikov, O. and Karwowski, H. J. and Markoff, D. M. and Tornow, W. and Heeger, K. M. and Piquemal, F. and Ricol, J.-S (2008) Precision measurement of neutrino oscillation parameters with KamLAND. Physical Review Letters, 100 (22). p. 221803. ISSN 0031-9007. doi:10.1103/PhysRevLett.100.221803.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


The KamLAND experiment has determined a precise value for the neutrino oscillation parameter Δm2 21 and stringent constraints on θ12. The exposure to nuclear reactor antineutrinos is increased almost fourfold over previous results to 2:44 x 10 32 proton yr due to longer livetime and an enlarged fiducial volume. An undistorted reactor ∇e energy spectrum is now rejected at >5σ. Analysis of the reactor spectrum above the inverse beta decay energy threshold, and including geoneutrinos, gives a best fit at Δm2 21= 7.58+0.14-0.13(stat)+0.15-0.15(syst)x10-5 eV2 and tan 2θ 2=0.56+0.10-0.07(stat)+0.10-0.06(syst). Local Δχ2 minima at higher and lower Δm2 21 are disfavored at >4σ. Combining with solar neutrino data, we obtain Δm2 21 7.59+0.21-0.21 X 10-5 eV2 and tan2θ12=0.47+0.06-0.05.

Item Type:Article
Related URLs:
URLURL TypeDescription
Kozlov, A.0000-0002-6679-3985
Vogel, P.0000-0003-0587-5466
Additional Information:© 2008 The American Physical Society.(Received 29 January 2008; published 5 June 2008). The KamLAND experiment is supported by the Japanese Ministry of Education, Culture, Sports, Science and Technology, and under the United States Department of Energy Office Grant No. DEFG03-00ER41138 and other DOE grants to individual institutions. The reactor data are provided by courtesy of the following electric associations in Japan: Hokkaido, Tohoku, Tokyo, Hokuriku, Chubu, Kansai, Chugoku, Shikoku, and Kyushu Electric Power Companies, Japan Atomic Power Co., and Japan Nuclear Cycle Development Institute. The Kamioka Mining and Smelting Company has provided service for activities in the mine. PACS: 14.60.Pq; 26.65.+t; 28.50.Hw; 91.35.-x
Funding AgencyGrant Number
Ministry of Education, Culture, Sports, Science and Technology (MEXT)UNSPECIFIED
Department of Energy Office (DOE)DE-FG03-00ER41138
Subject Keywords:Neutrino mass and mixing; Solar neutrinos in nuclear astrophysics; Power and production reactors; Earth's interior structure and properties
Issue or Number:22
Record Number:CaltechAUTHORS:20090409-152721420
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:13914
Deposited By: Ruth Sustaita
Deposited On:03 Aug 2009 21:07
Last Modified:08 Nov 2021 22:41

Repository Staff Only: item control page