Revisiting charmless two-body B decays involving eta ' and eta

We have studied charmless two-body B decays involving eta and eta ' in the framework of QCD improved factorization approach. The spectator hard scatte ring mechanism for eta ' production have been re-examined and extended, whi ch contributions are incorporated consistently into the factorizable leadin g contributions. It is found that the conventional mechanism would give Br( B --> eta 'K) similar to 30 x 10(-6) which agrees with predictions based on naive factorization approaches. With the incorporation of spectator hard s cattering mechanism contributions, theoretical predictions are improved muc h and the bulk of Br(B --> eta 'K) are accommodated in the reasonable param eter space. We have also presented calculations of g*g* - eta(') transition form factors within the standard hard scattering approach. It is shown tha t the new contributions in the modes such as B --> eta ' + vector and B --> eta + pi, rho, K ((*)) are small. Direct CP-violation in those decay modes are predicted. It is shown that the prospects for measuring direct CP-viol ation effects in B+/- --> eta 'K+/- , eta ' pi +/-, eta pi (+/-), and etaK( +/-) are promising at B factories in the near future. (C) 2001 Elsevier Sci ence B.V. All rights reserved.