Measurements of Absolute Branching Fractions for Exclusive $D^0$ Semileptonic Decays

Abstract

Based on a data sample of 60 pb$^{-1}$ collected at the $\psi(3770)$ resonance with the CLEO-c detector at CESR, we present improved measurements of absolute branching fractions for exclusive $D^0$ semileptonic decays into $K^-e^+\nu$, $\pi^-e^+\nu$ and $K^{*-}e^+\nu$, and the first observation and measurement of $D^0 \to \rho^-e^+\nu$. The determinations of the CKM matrix elements $V_{cs}$ and $V_{cd}$ are reviewed.