${{\mathit \tau}}$-DECAY PARAMETERS

($\xi \kappa )({{\mathit e}}$) PARAMETER

INSPIRE   JSON  (beta) PDGID:
S035XKE
($\mathit V−\mathit A$) theory predicts ($\xi \kappa )({{\mathit e}}$) = 0.
VALUE EVTS DOCUMENT ID TECN  COMMENT
$-0.4$ $\pm0.8$ $\pm0.9$ 78k 1, 2
SHIMIZU
2018A
 BELL ${{\mathit \tau}^{-}}$ $\rightarrow$ ${{\mathit \nu}_{{{\tau}}}}{{\mathit e}^{-}}{{\overline{\mathit \nu}}_{{{e}}}}{{\mathit \gamma}}$
1  SHIMIZU 2018A measurement procedure fits a distribution affected by ${{\overline{\mathit \eta}}}({{\mathit e}}$), ($\xi \kappa )({{\mathit e}}$) and ${{\mathit \eta}^{''}}({{\mathit e}}$), floating ($\xi \kappa )({{\mathit e}}$) and fixing ${{\overline{\mathit \eta}}}({{\mathit e}}$) = 0 and ${{\mathit \eta}^{''}}({{\mathit e}}$) = 0. The contribution of ${{\mathit \eta}^{''}}({{\mathit e}}$) is suppressed by ${\mathit m}_{{{\mathit e}}}/{\mathit m}_{{{\mathit \tau}}}$.
2  Error correlated with SHIMIZU 2018A ($\xi \kappa )({{\mathit e}}$ or ${{\mathit \mu}}$) value.
References