Rho-Omega Mixing and Direct CP Violation in Hadronic B-Decays

The extraction of CKM-matrix-element information from hadronic B-decays generally suffers from discrete ambiguities, hampering the diagnosis of physics beyond the Standard Model. We show that a measurement of the rate asymmetry, which is CP-violating, in $B^{\pm}\to\rho^{\pm}\rho^0(\omega)\to\rho^{\pm}\pi^+\pi^-$, where the invariant mass of the $\pi^+\pi^-$ pair is in the vicinity of the $\omega$ resonance, can remove the mod($\pi$) uncertainty in $\alpha\equiv arg [-V_{td} V_{tb}^\ast/(V_{ud}V_{ub}^\ast)]$ present in standard analyses.