Study of the Semileptonic Charm Decays ${D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\ell}}^{+}\ensuremath{\nu}$ and ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\ell}}^{+}\ensuremath{\nu}$

Study of the Semileptonic Charm Decays $D^{0} \to π^{-} ℓ^{+} ν$ and $D^{0} \to K^{-} ℓ^{+} ν$

G. S. Huang et al. (CLEO Collaboration)

Phys. Rev. Lett. 94, 011802 – Published 6 January 2005

Abstract

We investigate the decays $D^{0} \to π^{-} ℓ^{+} ν$ and $D^{0} \to K^{-} ℓ^{+} ν$ , where $ℓ$ is $e$ or $μ$ , using approximately $7 {f b}^{- 1}$ of data collected with the CLEO III detector. We find $R_{0} \equiv B (D^{0} \to π^{-} e^{+} ν) / B (D^{0} \to K^{-} e^{+} ν) = 0.082 \pm 0.006 \pm 0.005$ . Fits to the kinematic distributions of the data provide parameters describing the form factor of each mode. Combining the form factor results and $R_{0}$ gives $| f_{+}^{π} (0) |^{2} | V_{c d} |^{2} / | f_{+}^{K} (0) |^{2} | V_{c s} |^{2} = {0.038}_{- 0.007 - 0.003}^{+ 0.006 + 0.005}$ .