Measurement of the relative B−→D0/D*0/D**0μ−ν¯μ branching fractions using B− mesons from B¯s2*0 decays

Le résumé fourni par la source

The decay of the narrow resonance ${\overline{B}}_{s2}^{*0}\ensuremath{\rightarrow}{B}^{\ensuremath{-}}{K}^{+}$ can be used to determine the ${B}^{\ensuremath{-}}$ momentum in partially reconstructed decays without any assumptions on the decay products of the ${B}^{\ensuremath{-}}$ meson. This technique is employed for the first time to distinguish contributions from ${D}^{0}$, ${D}^{*0}$, and higher-mass charmed states (${D}^{**0}$) in semileptonic ${B}^{\ensuremath{-}}$ decays by using the missing-mass distribution. The measurement is performed using a data sample corresponding to an integrated luminosity of $3.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected with the LHCb detector in $pp$ collisions at center-of-mass energies of 7 and 8 TeV. The resulting branching fractions relative to the inclusive ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{0}X{\ensuremath{\mu}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$ are ${f}_{{D}^{0}}=\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\mu}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})/\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{0}X{\ensuremath{\mu}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})=\phantom{\rule{0ex}{0ex}}0.25\ifmmode\pm\else\textpm\fi{}0.06,{f}_{{D}^{**0}}=\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}({D}^{**0}\ensuremath{\rightarrow}{D}^{0}X){\ensuremath{\mu}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})/\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{0}X{\ensuremath{\mu}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})=0.21\ifmmode\pm\else\textpm\fi{}0.07,$ with ${f}_{{D}^{*0}}=1\ensuremath{-}{f}_{{D}^{0}}\ensuremath{-}{f}_{{D}^{**0}}$ making up the remainder.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.