Measurement of D[superscript 0]-D̅[superscript 0] mixing and CP violation in two-body D[superscript 0] decays

Abstract

We present a measurement of D[superscript 0]-D̅[superscript 0] mixing and CP violation using the ratio of lifetimes simultaneously extracted from a sample of D[superscript 0] mesons produced through the flavor-tagged process D[superscript *+]→D[superscript 0]π[superscript +], where D[superscript 0] decays to K[superscript ∓]π[superscript ±], K[superscript -]K[superscript +], or π[superscript -]π[superscript +], along with the untagged decays D[superscript 0]→K[superscript ∓]π[superscript ±] and D[superscript 0]→K[superscript -]K[superscript +]. The lifetimes of the CP-even, Cabibbo-suppressed modes K[superscript -]K[superscript +] and π[superscript -]π[superscipt +] are compared to that of the CP-mixed mode K[superscript ∓]π[superscript ±] in order to measure y[subscript CP] and ΔY. We obtain y[subscript CP]=[0.72±0.18(stat)±0.12(syst)]% and ΔY=[0.09±0.26(stat)±0.06(syst)]%, where ΔY constrains possible CP violation. The y[subscript CP] result excludes the null mixing hypothesis at 3.3σ significance. This analysis is based on an integrated luminosity of 468 fb[superscript -1] collected with the BABAR detector at the PEP-II asymmetric-energy e[superscript +]e[superscript -] collider.