Possibility of Large Final State Interaction Phases in Light of B \to Kπand ππData

Abstract

The newly observed $\bar B^0 \to \bar K^0π^0$ mode is quite sizable while $π^-π^+$ is rather small. Data also hint at $π^-π^0 \gtrsim π^-π^+$. Though consistent with zero, central values of CP violating asymmetries in $K^-π^{+,0}$ and $\bar K^0π^-$ show an interesting pattern. Taking cue from these, we suggest that, besides $γ\equiv {\rm arg} (V_{ub}^*)$ being large, the rescattering phase $δ$ in $Kπ$ and $ππ$ modes may be greater than $90^\circ$. If this is true, not only the above trends can be accounted for, one would also find $π^0π^0 \sim π^-π^{+,0}$, and the CP asymmetry in $\bar B^0$ vs. $B^0 \to π^-π^+$ could be as large as -60%. These results can be tested in a couple of years.