Implications of CP Asymmetry Limits for $B \to K π$ and $B \to ππ$

Abstract

Recent experimental limits for the direct CP asymmetries in $B^0 \to K^+ π^-$, $B^+ \to K^+ π^0$, $B^+ \to K^0 π^+$, and $B^0 \to π^+ π^-$, and for the indirect CP asymmetry in $B^0 \to π^+ π^-$, are combined with information on CP-averaged branching ratios to shed light on weak and strong phases. At present such bounds favor $γ\ge 60^\circ$ at the $1 σ$ level. The prospects for further improvements are discussed.