Improved constraints on D0-D0 mixing in D0 --> K+ pi- decays from the Belle detector.
We report the results of a search for D0-D0 mixing in D0 --> K+ pi- decays based on 400 fb(-1) of data accumulated by the Belle detector at KEKB. Both assuming CP conservation and allowing for CP violation, we fit the decay-time distribution for the mixing parameters x and y, as well as for the parameter R(D), the ratio of doubly Cabibbo-suppressed decays to Cabibbo-favored decays. The 95% confidence level region in the (x'2,y') plane is obtained using a frequentist method. Assuming CP conservation, we find x'2 < 0.72 x 10(-3) and -9.9 x 10(-3) < y' < 6.8 x 10(-3) at the 95% confidence level; these are the most stringent constraints on the mixing parameters to date. The no-mixing point (0,0) has a confidence level of 3.9%. Assuming no mixing, we measure R(D) = (0.377 +/- 0.008 +/- 0.005)%.
Zhang
L M
LM
University of Science and Technology of China, Hefei.
Zhang
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Li
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Abe
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Abe
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Adachi
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Aihara
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Anipko
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Arinstein
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Asano
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Barbero
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Bitenc
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Bizjak
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Bozek
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Bracko
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Brodzicka
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Browder
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Chang
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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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Choi
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Choi
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Choi
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Chuvikov
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Cole
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Dalseno
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Danilov
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Dash
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Drutskoy
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Eidelman
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Gabyshev
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Hara
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Hastings
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Hayashii
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Hazumi
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Hoshi
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Hou
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Hou
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Hsiung
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Iijima
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Ikado
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Inami
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Ishikawa
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Itoh
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Iwasaki
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Iwasaki
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Kang
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Katayama
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Kawai
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Kawasaki
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Kichimi
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Kim
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Kim
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Kim
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Kinoshita
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Korpar
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Krizan
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Krokovny
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Kulasiri
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Kumar
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Kuo
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Kwon
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Leder
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Lee
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Lesiak
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Lin
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Liventsev
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Mandl
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Matsumoto
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Mikami
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Mitaroff
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Miyabayashi
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Miyake
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Miyata
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Miyazaki
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Mizuk
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Mohapatra
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Mori
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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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Okabe
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Okuno
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Olsen
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Ostrowicz
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Ozaki
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Park
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Park
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Satoyama
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Schneider
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Schwartz
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Seidl
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Senyo
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Sevior
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Shapkin
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Shibuya
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Shwartz
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Singh
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Sumisawa
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Sumiyoshi
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Suzuki
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Takasaki
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Tamai
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Tamura
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Tanaka
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Taylor
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Teramoto
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Tian
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Trabelsi
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Tsuboyama
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Tsukamoto
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Uehara
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Urquijo
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Usov
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Varner
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Villa
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Wang
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Watanabe
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Xie
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Yamauchi
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Ying
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Yuan
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Zhang
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Zhang
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Zhilich
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Zürcher
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