Measurement of the CP-violation parameter sin2φ1 with a new tagging method at the Υ(5S) resonance.
We report a measurement of the CP-violation parameter sin2φ1 at the Υ(5S) resonance using a new tagging method, called "B-π tagging." In Υ(5S) decays containing a neutral B meson, a charged B, and a charged pion, the neutral B is reconstructed in the J/ψK(S)(0) CP-eigenstate decay channel. The initial flavor of the neutral B meson at the moment of the Υ(5S) decay is opposite to that of the charged B and may thus be inferred from the charge of the pion without reconstructing the charged B. From the asymmetry between B-π(+) and B-π(-) tagged J/ψK(S)(0) yields, we determine sin2φ1=0.57±0.58(stat)±0.06(syst). The results are based on 121 fb(-1) of data recorded by the Belle detector at the KEKB e(+)e(-) collider.
Tohoku University, Sendai, Japan.
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Sato
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Aihara
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Aulchenko
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Aushev
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Aziz
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Bhardwaj
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Bhuyan
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Bischofberger
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Bozek
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Bračko
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Chen
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Haba
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Hara
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Hayasaka
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Hayashii
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Kim
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Kinoshita
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Kwon
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Lange
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Lee
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Li
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Li
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Liu
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Liu
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Nakao
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Sumiyoshi
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Tanaka
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Teramoto
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Trabelsi
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Uchida
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Wicht
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Yamashita
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Yusa
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Zhang
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