Journal article

Measurements of branching fractions and time-dependent CP-violating asymmetries in B -> eta ' K decays

B Aubert, R Barate, D Boutigny, F Couderc, Y Karyotakis, JP Lees, V Poireau, V Tisserand, A Zghiche, E Grauges-Pous, A Palano, A Pompili, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, I Ofte, B Stugu Show all

PHYSICAL REVIEW LETTERS | AMER PHYSICAL SOC | Published : 2005

Abstract

We present measurements of the B --> eta(')K branching fractions; for B(+) --> eta(')K(+) we measure also the time-integrated charge asymmetry Alpha(ch), and for B(0) --> eta(')K(0)(S) the time-dependent CP-violation parameters S and C. The data sample corresponds to 232 x 10(6) BB pairs produced by e(+)e(-) annihilation at the Upsilon (4S). The results are Beta(B --> eta(')K(+)) = (68.9 +/- 2.0 +/- 3.2) x 10(-6), Beta(B(0) --> eta(')K(0)) = (67.4 +/- 3.2) x 10(-6), Alpha(ch) = 0.033 +/- 0.028 +/- 0.005, S = 0.30 +/- 0.140 +/- 0.02, and C = -0.21 +/- 0.10 +/- 0.02, where the first error quoted is statistical and the second is systematic.

Grants

Funding Acknowledgements

We thank the KEKB group for excellent operation of the accelerator; the KEK cryogenics group for efficient sole-noid operations; and the KEK computer group, the NII, and PNNL/EMSL for valuable computing and SINET4 network support. We acknowledge support from MEXT, JSPS and Nagoya's TLPRC (Japan); ARC and DIISR (Australia); NSFC (China); MSMT (Czechia); DST (India); INFN (Italy); MEST, NRF, GSDC of KISTI, and WCU (Korea); MNiSW (Poland); MES and RFAAE (Russia); ARRS (Slovenia); SNSF (Switzerland); NSC and MOE (Taiwan); and DOE and NSF (USA).