Observation of B_(s)(0)-->phigamma and search for B_(s)(0)-->gammagamma decays at Belle.
We search for the radiative penguin decays B_{s}{0}-->varphigamma and B_{s}{0}-->gammagamma in a 23.6 fb{-1} data sample collected at the Upsilon(5S) resonance with the Belle detector at the KEKB e{+}e{-} asymmetric-energy collider. We observe for the first time a radiative penguin decay of the B_{s}{0} meson in the B_{s}{0}-->varphigamma mode and we measure B(B_{s}{0}-->varphigamma)=(57_{-15}{+18}(stat)-11+12(syst))x10{-6}. No significant B_{s}{0}-->gammagamma signal is observed and we set a 90% confidence level upper limit of B(B_{s}{0}-->gammagamma)<8.7x10{-6}.
Budker Institute of Nuclear Physics, Novosibirsk.
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Wicht
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Adachi
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Aihara
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Arinstein
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Aulchenko
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Bakich
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Balagura
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Bay
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Belous
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Bhardwaj
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Bitenc
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Bondar
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Bozek
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Bracko
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Browder
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Chang
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Chao
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Chen
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Chen
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Cheon
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Chistov
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Cho
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Choi
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Dalseno
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Dash
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Drutskoy
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Eidelman
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Gabyshev
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Goldenzweig
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Golob
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Hazumi
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Hoshi
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Hyun
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Iijima
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Inami
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Ishikawa
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Ishino
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Itoh
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Iwasaki
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Kah
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Kaji
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Kang
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Kapusta
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Kawai
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Kim
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Kinoshita
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Liu
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Liventsev
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Mandl
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McOnie
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Medvedeva
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Mitaroff
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Miyazaki
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Mizuk
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Mohapatra
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Moloney
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Nakao
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Natkaniec
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Nishida
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Nitoh
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Nozaki
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Ogawa
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Ohshima
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Okuno
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Ozaki
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Pakhlov
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Pakhlova
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Palka
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Park
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Park
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Park
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Pestotnik
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Piilonen
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Sakai
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Schneider
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Schümann
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Schwartz
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Senyo
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Shapkin
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Shibuya
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Shiu
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Shwartz
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Singh
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Stanic
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Staric
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Sumisawa
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Sumiyoshi
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Takasaki
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Tamai
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Tanaka
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Taylor
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Teramoto
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Trabelsi
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Tsuboyama
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Uehara
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Ueno
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Ushiroda
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Usov
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Varner
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Vervink
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Villa
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Watanabe
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Won
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Yamashita
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Yamauchi
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Yusa
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Zhang
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Zhilich
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Zupanc
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Zwahlen