D~0 MIXING AT BABAR

摘要

The parameters x=Δm/T and y=ΔΓ/2Γ governing the mixing in the D~0-D~0 system can be constrained by analyzing hadronic decay modes of the D~0 meson. The lifetime difference between the D~0→K~- K~+ and the D~0→K~-π~+ decay modes measures y =-1.0 +- 2.2 (stat) +- 1.7(syst)% (preliminary) using 12.4 fb~(-1) of 2001 data. The D~0 meson can also decay to the wrong sign K~+π~- state either through a doubly Cabibbo suppressed decay or via mixing to the D~0 state followed by the Cabibbo favored decay D~0→K~+π~-. We give our sensitivity to x and y parameters, from the study of the time dependence of the wrong sign decay rate relative to the Cabibbo favored decay., obtained with 23.2 fb~(-1) of 1999-2000 data. We give a preliminary measurement of the wrong sign decay rate integrated over time, 0.38 +- 0.04 (stat) +- 0.02 (syst) %.