Measurement of CP violation and constraints on the CKM angle γ in B[superscript ±] → DK[superscript ±] with D → K[0 over S] π [superscript +] π[superscript -] decays

Abstract

A model-dependent amplitude analysis of B[superscript ±] → DK[superscript ±] with D→K[0 over S] π[superscript +] π[superscript −] decays is performed using proton–proton collision data, corresponding to an integrated luminosity of 1 fb[superscript −1], recorded by LHCb at a centre-of-mass energy of 7 TeV in 2011. Values of the CP violation observables x[subscript ±] and y[subscript ±], which are sensitive to the CKM angle γ, are measured to be x[subscript −] = +0.027 ± 0.044 [+0.010 over −0.008] ± 0.001, y[subscript −] = +0.013 ± 0.048[+0.009 over −0.007] ± 0.003, x[subscript +] = −0.084 ± 0.045 ± 0.009 ± 0.005, y[subscript +] = −0.032 ± 0.048[+0.010 over −0.009] ± 0.008, where the first uncertainty is statistical, the second systematic and the third arises from the uncertainty of the D→K[0 over S]π[superscript +]π[superscript −] amplitude model. The value of γ is determined to be (84[+49 over −42])°, including all sources of uncertainty. Neutral D meson mixing is found to have negligible effect.