Measurements of branching fraction ratios and CP-asymmetries in suppressed B-→D(→K+π-)K- and B-→D(→K+π-)π- decays

Abstract

We report the first reconstruction in hadron collisions of the suppressed decays B-→D(→K+π-)K- and B-→D(→K+π-)π-, sensitive to the Cabibbo-Kobayashi-Maskawa phase γ, using data from 7 fb-1 of integrated luminosity collected by the CDF II detector at the Tevatron collider. We reconstruct a signal for the B-→D(→K+π-)K- suppressed mode with a significance of 3.2 standard deviations, and measure the ratios of the suppressed to favored branching fractions R(K)=[22.0±8.6(stat)±2.6(syst)]×10-3, R+(K)=[42.6±13.7(stat)±2.8(syst)]×10-3, R-(K)=[3.8±10.3(stat)±2.7(syst)]×10-3 as well as the direct CP-violating asymmetry A(K)=-0.82±0.44(stat)±0.09(syst) of this mode. Corresponding quantities for B-→D(→K+π-)π- decay are also reported.