Search for the invisible decay of neutrons with KamLAND.
The Kamioka Liquid scintillator Anti-Neutrino Detector is used in a search for single neutron or two-neutron intranuclear disappearance that would produce holes in the -shell energy level of (12)C nuclei. Such holes could be created as a result of nucleon decay into invisible modes (inv), e.g., n--> 3v or nn--> 2v. The deexcitation of the corresponding daughter nucleus results in a sequence of space and time-correlated events observable in the liquid scintillator detector. We report on new limits for one- and two-neutron disappearance: tau(n--> inv) > 5.8 x 10(29) years and tau (nn--> inv) > 1.4 x 10(30) years at 90% C.L. These results represent an improvement of factors of approximately 3 and >10(4) and over previous experiments.
Araki
T
T
Research Center for Neutrino Science, Tohoku University, Sendai 980-8578, Japan.
Enomoto
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Furuno
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Gando
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Ichimura
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Ikeda
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Inoue
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Kishimoto
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Koga
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Koseki
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Maeda
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Mitsui
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Motoki
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Nakajima
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Nakamura
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Ogawa
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Ogawa
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Owada
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Ricol
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JS
Shimizu
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I
Shirai
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J
Suekane
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F
Suzuki
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A
Tada
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Takeuchi
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Tamae
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Tsuda
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Y
Watanabe
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Busenitz
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Classen
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Djurcic
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Keefer
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Leonard
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DS
Piepke
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A
Yakushev
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Berger
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BE
Chan
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YD
Decowski
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MP
Dwyer
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DA
Freedman
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SJ
Fujikawa
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Goldman
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Gray
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Heeger
K M
KM
Hsu
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L
Lesko
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KT
Luk
K-B
KB
Murayama
H
H
O'Donnell
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T
Poon
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AW
Steiner
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HM
Winslow
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LA
Jillings
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Mauger
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C
McKeown
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RD
Vogel
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Zhang
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C
Lane
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CE
Miletic
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Guillian
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Learned
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Maricic
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Matsuno
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Pakvasa
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Horton-Smith
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GA
Dazeley
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Hatakeyama
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Rojas
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Svoboda
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R
Dieterle
B D
BD
Detwiler
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Gratta
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Ishii
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Tolich
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Uchida
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Y
Batygov
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Bugg
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Efremenko
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Kamyshkov
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Y
Kozlov
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A
Nakamura
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Karwowski
H J
HJ
Markoff
D M
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Rohm
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Tornow
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Wendell
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R
Chen
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MJ
Wang
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Piquemal
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