$\beta ({\varphi }_1)$ from $B$ Decays to Charm

Abstract

The measurement of $\sin 2\beta$ from $B_d\to J/\psi K_s$ does not resolve the discrete ambiguities in the angle $\beta$. A measurement of $\cos 2\beta$ is therefore desirable.This talk is about measuring the CKM angle $\beta ({\varphi }_1)$ from various B decays to charm final states which also allow us a measurement of $\cos 2\beta$.

4 pages, 4 figures. Added references. Talk presented at CKM2006 Workshop, Nagoya, Japan