We present a measurement of $D^0$-$\D0bar$ mixing parameters using the ratios of lifetimes extracted from samples of $D^0$ mesons decaying to $K^-\pi^+$, $K^-K^+$, and $\pi^-\pi^+$. Using 91 ${ \rm fb}^{ -1}$ of data collected by the BaBar detector at the PEP-II asymmetric-energy $B$ Factory, we obtain a value $Y = (0.8 \pm 0.4 ({ \rm stat.}) { }^{ +0.5}_{ -0.4} ({ \rm syst.}))$%, which, in the limit of CP conservation, corresponds to the mixing parameter $y = \Delta\Gamma/2\Gamma$. Using the difference in lifetimes of $D^0$ and $\D0bar$ mesons, we obtain the CP-violation parameter $\Delta Y = (-0.8 \pm 0.6 ({ \rm stat.}) \pm 0.2 ({ \rm syst.}))$%.
Categories: hep-ex