Testing the Standard Model of CP Violation in the B System

Abstract

We review the subject of CP violation in the $B$ meson system within the Standard Model of CP violation, which is based on a complex phase in the Cabibbo-Kobayashi-Maskawa (CKM) matrix. Three kinds of CP nonconservation are studied: In $B^0-\Bbar$ mixing, in mixed neutral $B$ decays to states which are common decay products of $B^0$ and $\Bbar$ and in direct decays of charged $B$ mesons. Measurements of certain CP asymmetries are shown to determine the three angles of the CKM unitarity triangle. $\beta$ is measured cleanly in $B^0\to\psi K_S$. Uncertainties due to penguin amplitudes in the determination of $\alpha$ using the asymmetry in $B^0\to \pi^+\pi^-$ (or $B^0 \to \rho^+\pi^-$) can be eliminated (or in the worst case only estimated) by relating the rate of this process to decay rates involving other two light pseudoscalars. The angle $\gamma$ can be measured in charged $B$ decays, provided that color suppression in $B\to DK$ (or $B\to DK_i(1400)$) is not too strong and/or that certain rescattering effects in $B$ decays to two light pseudoscalars are not too large.