Search for proton decay via p-->e+pi0 and p-->micro+pi0 in a large water Cherenkov detector.
We have searched for proton decays via p-->e;{+}pi;{0} and p-->micro;{+}pi;{0} using data from a 91.7 kt.yr exposure of Super-Kamiokande-I and a 49.2 kt.yr exposure of Super-Kamiokande-II. No candidate events were observed with expected backgrounds induced by atmospheric neutrinos of 0.3 events for each decay mode. From these results, we set lower limits on the partial lifetime of 8.2 x 10;{33} and 6.6 x 10;{33} years at 90% confidence level for p-->e;{+}pi;{0} and p-->micro;{+}pi;{0} modes, respectively.
Nishino
H
H
Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan.
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Abe
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Hayato
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Iida
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Ikeda
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Kameda
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Kobayashi
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Koshio
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Miura
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Moriyama
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Nakahata
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Nakayama
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Obayashi
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Ogawa
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Sekiya
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Shiozawa
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Suzuki
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Takeda
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Takenaga
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Takeuchi
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Ueno
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Ueshima
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Watanabe
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Yamada
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Hazama
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Higuchi
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Ishihara
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Kajita
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Kaneyuki
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Mitsuka
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Okumura
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Tanimoto
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Vagins
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Dufour
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Kearns
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Litos
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Raaf
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Stone
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Sulak
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Wang
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Goldhaber
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Dazeley
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Svoboda
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Bays
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Casper
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Cravens
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Kropp
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Mine
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Regis
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Smy
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Sobel
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Ganezer
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Hill
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Keig
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Jang
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Kim
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Lim
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Fechner
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Scholberg
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Walter
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Wendell
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Tasaka
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Learned
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Matsuno
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Watanabe
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Hasegawa
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Ishida
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Kobayashi
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Nakadaira
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Nakamura
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Nishikawa
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Oyama
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Sakashita
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Sekiguchi
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Tsukamoto
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Suzuki
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Minamino
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Nakaya
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Yokoyama
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Fukuda
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Itow
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Tanaka
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Jung
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Lopez
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McGrew
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Terri
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Yanagisawa
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Tamura
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Idehara
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Sakuda
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Kuno
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Yoshida
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Kim
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Yang
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Ishizuka
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Okazawa
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Choi
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Seo
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Furuse
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Nishijima
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Yokosawa
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Koshiba
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Totsuka
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Chen
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Heng
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Yang
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Zhang
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Kielczewska
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Thrane
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Wilkes
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