EXPERIMENTAL TESTS OF FACTORIZATION IN CHARMLESS NONLEPTONIC 2-BODY B-DECAYS - ART. NO. 094009

Using a theoretical framework based on the next-to-leading-order QCD-i mproved effective Hamiltonian and a factorization ansatz for the hadro nic matrix elements of the four-quark operators, we reassess branching fractions in two-body nonleptonic decays B --> PP,PV,VV, involving th e lowest-lying light pseudoscalar (P) and Vector (V) mesons in the sta ndard model. We work out the parametric dependence of the decay rates, making use of the currently available information on the weak mixing matrix elements, form factors, decay constants, and quark masses. Usin g the sensitivity of the decay rates on the effective number of colors , N-c, as a criterion of theoretical predictivity, we classify all the current-current (tree) and penguin transitions in five different clas ses. The recently measured charmless two-body B --> PP decays (B+ --> K+ eta', B-0 --> K-0 eta', B-0 --> K+ pi(-), B+ --> pi(+) K-0, and cha rge conjugates) are dominated by the N-c-stable QCD penguin transition s (class-IV transitions) and their estimates are consistent with the d ata. The measured charmless B --> PV (B+ --> omega K+, B+ --> omega h( +)) and B --> VV transition (B --> phi K), on the other hand, belong to the penguin (class-V) and tree (class-III) transitions. The class-V penguin transitions are N-c sensitive and/or involve large cancellati ons among competing amplitudes, making their decay rates in general mo re difficult to predict. Some of these transitions may also receive si gnificant contributions from annihilation and/or final state interacti ons. We propose a number of tests of the factorization framework in te rms of the ratios of branching ratios for some selected B --> h(1)h(2) decays involving light hadrons h(1) and h(2), which depend only moder ately on the form factors. We also propose a set of measurements to de termine the effective coefficients of the current-current and QCD peng uin operators. The potential impact of B --> h(1)h(2) decays on the CK M phenomenology is emphasized by analyzing a number of decay rates in the factorization framework. [S0556-2821(98)05119-4]