Measurements of the τ mass and the mass difference of the τ+ and τ− atBABAR

Le résumé fourni par la source

We present the result from a precision measurement of the mass of the $\ensuremath{\tau}$ lepton, ${M}_{\ensuremath{\tau}}$, based on $423\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of data recorded at the $\ensuremath{\Upsilon}(4S)$ resonance with the BABAR detector. Using a pseudomass endpoint method, we determine the mass to be $1776.68\ifmmode\pm\else\textpm\fi{}0.12(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.41(\mathrm{syst})\text{ }\text{ }\mathrm{MeV}$. We also measure the mass difference between the ${\ensuremath{\tau}}^{+}$ and ${\ensuremath{\tau}}^{\ensuremath{-}}$, and obtain $({M}_{{\ensuremath{\tau}}^{+}}\ensuremath{-}{M}_{{\ensuremath{\tau}}^{\ensuremath{-}}})/{M}_{\mathrm{AVG}}^{\ensuremath{\tau}}=(\ensuremath{-}3.4\ifmmode\pm\else\textpm\fi{}1.3(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.3(\mathrm{syst}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, where ${M}_{\mathrm{AVG}}^{\ensuremath{\tau}}$ is the average value of ${M}_{{\ensuremath{\tau}}^{+}}$ and ${M}_{{\ensuremath{\tau}}^{\ensuremath{-}}}$.

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