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

Abstract

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

Comments: 6 pages, 1 figure, this is the last version to appear in Phys. Rev. D