pdgLive

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

$\xi ({{\mathit \pi}}$) PARAMETER

INSPIRE JSON (beta) PDGID:

($\mathit V−\mathit A$) theory predicts $\xi ({{\mathit \pi}}$) = $1$.

VALUE

EVTS

DOCUMENT ID

TECN

COMMENT

$\bf{ 0.993 \pm0.022}$

OUR FIT

$\bf{ 0.994 \pm0.023}$

OUR AVERAGE

$0.994$ $\pm0.020$ $\pm0.014$

27k

ALEP

1991--1995 LEP runs

$0.81$ $\pm0.17$ $\pm0.02$

SLD

1993--1995 SLC runs

$1.03$ $\pm0.06$ $\pm0.04$

2.0k

CLEO

${\it{}E}^{\it{}ee}_{\rm{}cm}$= $10.6$ GeV

• • We do not use the following data for averages, fits, limits, etc. • •

$0.987$ $\pm0.057$ $\pm0.027$

ALEP

Repl. by HEISTER 2001E

$0.95$ $\pm0.11$ $\pm0.05$

ALEP

1990+1991 LEP run

¹	Superseded by BUSKULIC 1995D.

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