CKM $\gamma$ phase from $B\to K\pi \pi$

Abstract

We discuss a method to extract the CKM $\gamma$ angle combining Dalitz plot analysis of $B^{\pm }\to K^{\pm }{\pi }^{+}{\pi }^{-}$ and untagged $B^0$, ${\bar{B}}^0\to K_s{\pi }^{+}{\pi }^{-}$. The method also allows obtaining the ratio and phase difference between the {\it tree} and {\it penguin} contributions from $B^0$ and ${\bar{B}}^0\to K^{\ast \pm }{\pi }^{\mp }$ decays and direct CP asymmetry between $B^0$ and $\overline{B^0}$. From Monte Carlo studies of 100K events for the neutral mesons, we show the possibility of measuring $\gamma$ with a precision of $\sim 5^o$.

4 pages, 2 figures. To appear in the proceedings of the 4th International Workshop on the CKM Unitarity Triangle, december 12-16 2006, Nagoya, Japan