Systematic Error on Weak Phase $\gamma$ from $B \to \pi^+ \pi^-$ and $B \to K \pi$

Understand

When CP asymmetries in $B^0(t)\to \pi^+ \pi^-$ are combined using broken flavor SU(3) with decay rates for $B^+\to K^0\pi^+$ and/or $B^0\to K^+\pi^-$, one can obtain stringent limits on the weak phase $\gamma$ which are consistent with those obtained from other CKM constraints.

• Experimental data in the past few years have improved to the extent that systematic errors associated with uncertainty in SU(3) symmetry breaking dominate the determination of $\gamma$.
• We obtain a value $\gamma =(73 \pm 4^{+10}_{-8})^\circ$, where the first error is statistical while the second one is systematic.