D^0-D^0bar mixing in \Upsilon(1S) \to D^0 D^0bar decay at Super-B

Abstract

$\Dz-\Dzb$ mixing and significant CP violation in the charm system may indicate the signature of new physics. In this study, we suggest that the coherent $\DzDzb$ events from the decay of $\Upsilon(1S) \to \Dz \Dzb$ can be used to measure both mixing parameters and CP violation in charm decays. The neutral $D$ mesons from $\Upsilon(1S)$ decay are strongly boosted, so that it will offer the possibility to measure the proper-time interval, $\Delta t$, between the fully-reconstructed $\Dz$ and $\Dzb$. Both coherent and time-dependent information can be used to extract $\Dz-\Dzb$ mixing parameters. The sensitivity of the measurement should be improved at B factories or super-B.