B→η′Xs in the standard model

We study B→η′Xs within the framework of the Standard Model. Several mechanisms such as b→η′sg through the QCD anomaly, and b→η′s and B→η′sq̄ arising from four-quark operators are treated simultaneously. Using QCD equations of motion, we relate the effective Hamiltonian for the first mechanism to that for the latter two. By incorporating next-to-leading-logarithmic(NLL) contributions, the first mechanism is shown to give a significant branching ratio for B→η′Xs, while the other two mechanisms account for about 15% of the experimental value. The Standard Model prediction for B→η′Xs is consistent with the CLEO data.