Precision measurement of neutrino oscillation parameters with KamLAND.


Journal Article

The KamLAND experiment has determined a precise value for the neutrino oscillation parameter Deltam21(2) and stringent constraints on theta12. 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 nu[over]e energy spectrum is now rejected at >5sigma. Analysis of the reactor spectrum above the inverse beta decay energy threshold, and including geoneutrinos, gives a best fit at Deltam21(2)=7.58(-0.13)(+0.14)(stat) -0.15+0.15(syst) x 10(-5) eV2 and tan2theta12=0.56(-0.07)+0.10(stat) -0.06+0.10(syst). Local Deltachi2 minima at higher and lower Deltam21(2) are disfavored at >4sigma. Combining with solar neutrino data, we obtain Deltam21(2)=7.59(-0.21)+0.21 x 10(-5) eV2 and tan2theta12=0.47(-0.05)+0.06.

Full Text

Duke Authors

Cited Authors

  • Abe, S; Ebihara, T; Enomoto, S; Furuno, K; Gando, Y; Ichimura, K; Ikeda, H; Inoue, K; Kibe, Y; Kishimoto, Y; Koga, M; Kozlov, A; Minekawa, Y; Mitsui, T; Nakajima, K; Nakamura, K; Nakamura, M; Owada, K; Shimizu, I; Shimizu, Y; Shirai, J; Suekane, F; Suzuki, A; Takemoto, Y; Tamae, K; Terashima, A; Watanabe, H; Yonezawa, E; Yoshida, S; Busenitz, J; Classen, T; Grant, C; Keefer, G; Leonard, DS; McKee, D; Piepke, A; Decowski, MP; Detwiler, JA; Freedman, SJ; Fujikawa, BK; Gray, F; Guardincerri, E; Hsu, L; Kadel, R; Lendvai, C; Luk, K-B; Murayama, H; O'Donnell, T; Steiner, HM; Winslow, LA; Dwyer, DA; Jillings, C; Mauger, C; McKeown, RD; Vogel, P; Zhang, C; Berger, BE; Lane, CE; Maricic, J; Miletic, T; Batygov, M; Learned, JG; Matsuno, S; Pakvasa, S; Foster, J; Horton-Smith, GA; Tang, A; Dazeley, S; Downum, KE; Gratta, G; Tolich, K; Bugg, W; Efremenko, Y; Kamyshkov, Y; Perevozchikov, O; Karwowski, HJ; Markoff, DM; Tornow, W; Heeger, KM; Piquemal, F; Ricol, J-S; KamLAND Collaboration,

Published Date

  • June 5, 2008

Published In

Volume / Issue

  • 100 / 22

Start / End Page

  • 221803 -

PubMed ID

  • 18643415

Pubmed Central ID

  • 18643415

Electronic International Standard Serial Number (EISSN)

  • 1079-7114

International Standard Serial Number (ISSN)

  • 0031-9007

Digital Object Identifier (DOI)

  • 10.1103/physrevlett.100.221803


  • eng