Measurement of the Strong Phase of $D^{0}\rightarrow K^{-}\pi^{+}$ Relative to $\bar{D^{0}}\rightarrow K^{-}\pi^{+}$ with CLEO-c Data

Quantum correlations in $\psi(3770) \rightarrow D^0 \bar{D^0}$ decays introduce sensitivity to charm mixing, doubly-Cabibbo-suppressed decay amplitudes, and strong phases into time-integrated $D^0$ and $\bar D^0$ decay rates. In this talk we describe the selection of CP-eigenstate $D^0$ and $\bar {D^0}$ tags in a sample of $\sim$300~pb$^{-1}$ of $e^+e^-$ annihilation data collected with the CLEO-c detector at the Cornell Electron Storage Ring. We use these tags and the quantum coherence of the $D^{0}\bar{D^{0}}$ pair to measure the rates for $D^{0}\rightarrow K^{-}\pi^{+}$ decays separately for CP-even and CP-odd states. We use the asymmetry between these rates to obtain a measurement of the relative strong phase $\delta$, which is an important ingredient for the interpretation of charm-mixing and CKM measurements at higher energies. Projections of the ultimate sensitivity for this determination with the full CLEO-c data sample are given.