Determination of the weak phase $\gamma$ from rate measurements in $B^{\pm} \to \pi K, \pi \pi$ decays

A method is described which, under the assumption of SU(3) symmetry, allows one to determine the angle $\gamma = Arg(V_{ub}^*)$ of the unitarity triangle from time-independent measurements of the branching ratios for the decays $B^+\to\pi^0 K^+$ and $B^-\to\pi^0 K^-$, as well as of the CP-averaged branching ratios for the decays $B^\pm\to\pi^\pm K^0$ and $B^\pm\to\pi^\pm\pi^0$. The effects of electroweak penguin operators are included in a model-independent way, and SU(3)-breaking corrections are accounted for in the factorization approximation.