Study ofD0-D¯0mixing

We present a study of $D^0$ mixing using events of the type $D^{\mathrm{*}+}$→${\pi }^{+}$ $D^0$, with $D^0$→$K^{+}$ ${\pi }^{\mathrm{-}}$ and $D^0$→$K^{+}$ ${\pi }^{\mathrm{-}}$ ${\pi }^{+}$ ${\pi }^{\mathrm{-}}$. The decay time is used to separate mixing from doubly Cabibbo-suppressed decays. We observe no evidence for mixing in either mode. Combining the results from the two decay modes, we find $r_M$=0.0005 ±0.0020 or $r_M$<0.0037 at the 90% confidence level, where $r_M$ is the ratio of wrong-sign decays from mixing to right-sign decays. We also present limits on doubly Cabibbo-suppressed decays and consider the effect of possible interference.