Angular distributions in the decay B→K*l+l−

Le résumé fourni par la source

We use a sample of $384\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ events collected with the BABAR detector at the PEP-II ${e}^{+}{e}^{\ensuremath{-}}$ collider to study angular distributions in the rare decays $B\ensuremath{\rightarrow}{K}^{*}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$, where ${\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ is either ${e}^{+}{e}^{\ensuremath{-}}$ or ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$. For low dilepton invariant masses, ${m}_{\ensuremath{\ell}\ensuremath{\ell}}<2.5\text{ }\text{ }\mathrm{GeV}/{c}^{2}$, we measure a lepton forward-backward asymmetry ${\mathcal{A}}_{\mathrm{FB}}={0.24}_{\ensuremath{-}0.23}^{+0.18}\ifmmode\pm\else\textpm\fi{}0.05$ and ${K}^{*}$ longitudinal polarization ${F}_{L}=0.35\ifmmode\pm\else\textpm\fi{}0.16\ifmmode\pm\else\textpm\fi{}0.04$. For ${m}_{\ensuremath{\ell}\ensuremath{\ell}}>3.2\text{ }\text{ }\mathrm{GeV}/{c}^{2}$, we measure ${\mathcal{A}}_{\mathrm{FB}}={0.76}_{\ensuremath{-}0.32}^{+0.52}\ifmmode\pm\else\textpm\fi{}0.07$ and ${F}_{L}={0.71}_{\ensuremath{-}0.22}^{+0.20}\ifmmode\pm\else\textpm\fi{}0.04$.

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