Phenomenological applications of QCD factorization to semi-inclusive B decays and direct CP violation - art. no. 114013

We systematically investigate the semi-inclusive B decals B-->MX, which are manifestations of the quark decay b-->Mq, within a framework inspired by Q CD-improved factorization. These decays are theoretically clean and have di stinctive experimental signatures. We focus on a class of these that do not require any form factor information, and therefore may be especially suita ble for extracting information on the angles alpha and gamma of the unitari ty triangle. The nonfactorizable effects, such as vertex-type and penguin-t ype corrections to the two-body b decay, b --> Mq, and hard spectator corre ctions to the three-body decay B --> Mq(1)(q) over bar (2) are calculable i n the heavy quark limit. QCD factorization is applicable when the emitted m eson is a light meson or a charmonium. We discuss the issue of the CPT cons traint on partial rate asymmetries. The strong phase coming from final-stat e rescattering due to hard gluon exchange between the final states can indu ce large rate asymmetries for tree-dominated color-suppressed modes (pi (o) , rho (o), omega )X-s(-). The nonfactorizable hard spectator interactions i n the three-body decay B-->Mq(1)(q) over bar (2), though phase-space suppre ssed, are extremely important for the tree-dominated modes (pi (o), rho (o) , omega )X-s(-), phiX, J/psiX(s), J/psiX and the penguin-dominated mode ome gaX(ss)(-). In fact, they are dominated by the hard spectator corrections. This is because the relevant hard spectator interaction is color allowed, w hereas the two-body semi-inclusive decays for these modes are color suppres sed. Our result for B(B-->J/psiX(s)) is in agreement with experiment. The s emi-inclusive decay modes (B) over bar (o)(s)--> (pi (o),rho (o), omega )X- s(-), rho X-o(ss)-, (B) over bar (o) -->(K-X, K*X-), and B- -->((KXs)-X-o, (KXs)-X-*o) are the most promising ones in searching for direct CP violatio n. In fact, they have branching ratios of order 10(-6) - 10(-4) and CP rate asymmetries of order (10-40)%. The decays (B) over bar (o)(s)--> (pi (o), rho (o), omega )X-ss(-) and B--->phiX are electroweak-penguin dominated. So me of them have sizable branching ratios and observable CP asymmetries.