Measurement of the CKM angle γ from a combination of B±→Dh± analyses

Abstract

A combination of three LHCb measurements of the CKM angle γ is presented. The decays B±→DK± and B±→Dπ± are used, where D denotes an admixture of D0 and D-0 mesons, decaying into K+K-, π+π-, K±π∓, K±π∓π±π∓, KS0π+π-, or KS0K+K- final states. All measurements use a dataset corresponding to 1.0 fb-1 of integrated luminosity. Combining results from B±→DK± decays alone a best-fit value of γ=72.0° is found, and confidence intervals are setγ∈[56.4,86.7]°at 68% CL,γ∈[42.6,99.6]°at 95% CL. The best-fit value of γ found from a combination of results from B±→Dπ± decays alone, is γ=18.9°, and the confidence intervalsγ∈[7.4,99.2]°∪[167.9,176.4]°at 68% CL are set, without constraint at 95% CL. The combination of results from B±→DK± and B±→Dπ± decays gives a best-fit value of γ=72.6° and the confidence intervalsγ∈[55.4,82.3]°at 68% CL,γ∈[40.2,92.7]°at 95% CL are set. All values are expressed modulo 180°, and are obtained taking into account the effect of D0-D-0 mixing. © 2013 CERN.