Study of the decays B0→D(*)+D(*)−

Le résumé fourni par la source

The decays ${B}^{0}\ensuremath{\rightarrow}{D}^{*+}{D}^{*\ensuremath{-}},$ ${B}^{0}\ensuremath{\rightarrow}{D}^{*\ifmmode\pm\else\textpm\fi{}}{D}^{\ensuremath{\mp}}$ and ${B}^{0}\ensuremath{\rightarrow}{D}^{+}{D}^{\ensuremath{-}}$ are studied in $9.7\ifmmode\times\else\texttimes\fi{}{10}^{6} \ensuremath{\Upsilon}(4\mathrm{S})\ensuremath{\rightarrow}B\overline{B}$ decays accumulated with the CLEO detector. We determine $\mathcal{B}{(B}^{0}\ensuremath{\rightarrow}{D}^{*+}{D}^{*\ensuremath{-}}{)=(9.9}_{\ensuremath{-}3.3}^{+4.2}[\mathrm{stat}]\ifmmode\pm\else\textpm\fi{}1.2[\mathrm{syst}])\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ and limit $\mathcal{B}{(B}^{0}\ensuremath{\rightarrow}{D}^{*\ifmmode\pm\else\textpm\fi{}}{D}^{\ensuremath{\mp}})<6.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ and $\mathcal{B}{(B}^{0}\ensuremath{\rightarrow}{D}^{+}{D}^{\ensuremath{-}})<9.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ at 90% confidence level (C.L.). We also perform the first angular analysis of the ${B}^{0}\ensuremath{\rightarrow}{D}^{*+}{D}^{*\ensuremath{-}}$ decay and determine that the $\mathrm{CP}$-even fraction of the final state is greater than $0.11$ at 90% C.L. Future measurements of the time dependence of these decays may be useful for the investigation of $\mathrm{CP}$ violation in neutral B meson decays.

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