## Abstract

The beauty to up quark coupling constant |V_{ub}| can be extracted from B→ρe^{+}ν_{e} combined with the form factors for D→K^{*}e^{+}ν_{e} and B→Vℓ^{+}ℓ^{-} and D→ρe^{+}ν _{e}. Using the entire CLEO-c ψ(3770)→DD̄ event sample, corresponding to an integrated luminosity of 818 pb^{-}1 and approximately 5.4×106 DD̄ events, we measure the form factors for the decays D0→ρ^{-}e^{+}ν_{e} and D ^{+}→ρ0e^{+}ν_{e} for the first time and the branching fractions with improved precision. A four-dimensional unbinned maximum likelihood fit determines the form factor ratios to be V(0)/A _{1}(0)=1.48±0.15±0.05 and A_{2}(0)/A _{1}(0)=0.83±0.11±0.04. Assuming Cabibbo-Kobayashi-Maskawa unitarity, the known D meson lifetimes, and our measured branching fractions we obtain the form factor normalizations A_{1}(0), A_{2}(0), and V(0). We also present a measurement of the branching fraction for D ^{+}→ωe^{+}ν_{e} with improved precision.

Original language | English (US) |
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Article number | 131802 |

Journal | Physical review letters |

Volume | 110 |

Issue number | 13 |

DOIs | |

State | Published - Mar 26 2013 |