Search for lepton-number- and baryon-number-violating tau decays at Belle

Le résumé fourni par la source

We search for lepton-number- and baryon-number-violating decays ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}\overline{p}{e}^{+}{e}^{\ensuremath{-}}$, $p{e}^{\ensuremath{-}}{e}^{\ensuremath{-}}$, $\overline{p}{e}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$, $\overline{p}{e}^{\ensuremath{-}}{\ensuremath{\mu}}^{+}$, $\overline{p}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$, and $p{\ensuremath{\mu}}^{\ensuremath{-}}{\ensuremath{\mu}}^{\ensuremath{-}}$ using $921\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of data, equivalent to $(841\ifmmode\pm\else\textpm\fi{}12)\ifmmode\times\else\texttimes\fi{}{10}^{6}$ ${\ensuremath{\tau}}^{+}{\ensuremath{\tau}}^{\ensuremath{-}}$ events, recorded with the Belle detector at the KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. In the absence of a signal, 90% confidence-level upper limits are set on the branching fractions of these decays in the range $(1.8\ensuremath{-}4.0)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}$. We set the world's first limits on the first four channels and improve the existing limits by an order of magnitude for the last two channels.

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