Measurement of the Relative Branching Fractions of Bbar --> D/D*/D** l^- anti-nu_l Decays in Events with a Fully Reconstructed B Meson

Abstract

We determine the relative branching fractions of semileptonic B decays to charmed final states. The measurement is performed on the recoil from a fully reconstructed B meson in a sample of 362 million BBbar pairs collected at the Upsilon(4S) resonance with the BaBar detector. A simultaneous fit to a set of discriminating variables is performed on a sample of Bbar --> D X l^- anti-nu_l decays to determine the contributions from the different channels. We measure Gamma(B- --> D l^- anti-nu_l)/Gamma (B- --> D X l^- anti-nu_l)= 0.227 +/- 0.014 +/- 0.016, Gamma(B- --> D* l^- anti-nu_l)/Gamma (B- --> D X l^- anti-nu_l)= 0.582 +/- 0.018 +/- 0.030 and Gamma(B- --> D** l^- anti-nu_l)/Gamma (B- --> D X l^- anti-nu_l)= 0.191 +/- 0.013 +/- 0.019 for the charged B sample, and Gamma(B0bar --> D l^- anti-nu_l)/Gamma (B0bar --> D X l^- anti-nu_l)= 0.215 +/- 0.016 +/- 0.013, Gamma(B0bar --> D* l^- anti-nu_l)/Gamma (B0bar --> D X l^- anti-nu_l)= 0.537 +/- 0.031 +/- 0.036 and Gamma(B0bar --> D** l^- anti-nu_l)/Gamma (B0bar --> D X l^- anti-nu_l)= 0.248 +/- 0.032 +/- 0.030 for the neutral B sample, where uncertainties are statistical and systematic, respectively.

8 pages, 1 postscript figure, submitted to PRD-RC

References in corpus (3)

• Big-Bang nucleosynthesis (Particle Data Group mini-review)
• The Cosmological Parameters 2006
• Measurement of the Ratio ${\cal B}\xspace(\B^+ \to X e ν)$ / ${\cal B}\xspace(\B^0 \to X e ν)

Cited by in corpus (8)

• Dalitz Plot Analysis of B- -> D+ pi- pi-
• Determination of the Form Factors for the Decay B0 -> D*- l+ nu_l and of the CKM Matrix Element |V_cb|
• Measurement of the Branching Fractions of Bbar -> D** l^- nubar_l Decays in Events Tagged by a Fully Reconstructed B Meson
• Measurement and interpretation of moments in inclusive semileptonic decays Bbar --> X_c l- nubar
• A Measurement of the Branching Fractions of exclusive Bbar -> D(*)(pi)l-nubar Decays in Events with a Fully Reconstructed B Meson
• Measurement of the Semileptonic Decays B --> D tau- nubar_tau and B --> D* tau- nubar_tau
• Measurement of the relative $B^{-}\to D^0/D^{\ast 0}/D^{\ast \ast 0}{\mu }^{-}{\overline{\nu }}_{\mu }$ branching fractions using $B^{-}$ mesons from $\overline{B}{}_{s2}^{\ast 0}$ decays
• An experimentalist's guide to the semileptonic bottom to charm branching fractions