Measurements of branching fractions and CP asymmetries in B -> eta h decays

作者：Chang P^*; Abe K; Abe K; Aihara H; Akatsu M; Asano Y; Aushev T; Bakich AM; Balagura V; Ban Y; Banerjee S; Bedny I; Bitenc U; Bizjak I; Blyth S; Bondar A; Bozek A; Bracko M; Brodzicka J; Browder TE; Chao Y; Chen A; Chen KF; Cheon BG; Chistov R; Choi SK; Choi Y; Chuvikov A; Cole S; Dalseno J; Danilov M; Dash M; Dragic J; Drutskoy A; Eidelman S; Eiges V; Fratina S; Gabyshev N; Garmash A; Gershon T; Gokhroo G; Guo R; Haba J; Hayasaka K; Hayashii H

来源：Physical Review D - Particles, Fields, Gravitation and Cosmology, 2005, 71(9): 091106.

DOI：10.1103/PhysRevD.71.091106

We report measurements of B to pseudoscalar-pseudoscalar decays with at least one eta meson in the final state using 140 fb(-1) of data collected by the Belle detector at KEKB e(+)e(-) collider. We observe the decay B+ -> eta pi(+) and find evidence of B+ -> eta K+; the measured branching fractions are B(B+ -> eta pi(+)) = (4.8(-0.7)(+0.8)(stat) +/- 0.3(sys)) x 10(-6) and B(B+ -> eta K+) = (2.1 +/- 0.6(stat) +/- 0.2(sys)) x 10(-6). Their corresponding CP violating asymmetries are measured to be 0.07 +/- 0.15(stat) +/- 0.03(sys) for eta pi(+/-) and -0.49 +/- 0.31(stat) +/- 0.07(sys) for eta K-+/-. No significant signals are found for neutral B -> eta h decays. We report the following upper limits on branching fractions at the 90% confidence level: B(B-0 -> eta K-0) < 2.0 x 10(-6), B(B-0 -> eta pi(0)) < 2.5 x 10(-6) and B(B-0 -> eta eta) < 2.0 x 10(-6).

• 出版日期2005-5
• 单位中国科学技术大学; 北京大学; 中央民族大学