Measurements of CP-violating asymmetries and branching fractions in B meson decays to eta ' K

We present measurements of the branching fractions of the decays B+ -> eta' K+ and B0 -> eta' K0. For B0 -> eta' K0s we also measure the time dependent CP-violation parameters S and C, and for B+ ->eta' K+ the time-integrated charge asymmetry Ach. The data sample corresponds to 88.9 million BBbar pairs produced by e+e- annihilation at the Upsillon(4S). The results are B(B+->eta'K+) = (76.9 +/- 3.5 +/- 4.4)*10^-6, B(B0->eta'K0) = (60.6 +/- 5.6 +/- 4.6)*10^-6, S = 0.02+/-0.34 +/- 0.03, C = 0.10+/-0.22 +/- 0.04, and Ach = 0.037 +/- 0.045+/- 0.011.