CP violation in charged B decays

CP violation in decay rates of, say, Bo → ψKs, important as they are, are primarily due to CP violation in the Bo bar Bo mass matrix. It is important to isolate CP violation that occurs in the decay process itself, since it provides independent checks on the mechanism of CP violation in nature. To this end, partial rate differences between B+ and B- would be particularly useful, since no mixing effects can occur, while complications such as effects of CP eigenstates in the final state would be absent as well. It is remarkable that CP violation can still arise, through interference effects between two amplitudes that have different CP-violating phases, as well as different final state interaction (FSI) phase shifts. In this paper, the author concentrates on the so-called penguin diagrams. Penguin diagrams provide both the ingredients for partial rate asymmetries. Being a loop diagram, it involves all three generations, each generation contributing with different KM elements. AT the same time, loop effects that involve real (on-shell) particle rescattering provide the necessary absorptive part (FSI phase). In what follows, the author reviews the subject of penguin-induced CP violation, with some emphasis on recent developments. Both inclusive and exclusive B± decays are discussed