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

$\rho ({{\mathit \mu}}$) PARAMETER

INSPIRE   JSON  (beta) PDGID:
S035RHM
($\mathit V−\mathit A$) theory predicts $\rho $ = $0.75$.
VALUE EVTS DOCUMENT ID TECN  COMMENT
$\bf{ 0.763 \pm0.020}$ OUR FIT
$\bf{ 0.770 \pm0.022}$ OUR AVERAGE
$0.776$ $\pm0.045$ $\pm0.019$ 46k
HEISTER
2001E
 ALEP 1991--1995 LEP runs
$0.999$ $\pm0.098$ $\pm0.045$ 22k
ABREU
2000L
 DLPH 1992--1995 runs
$0.777$ $\pm0.044$ $\pm0.016$ 27k
ACKERSTAFF
1999D
 OPAL 1990--1995 LEP runs
$0.69$ $\pm0.06$ $\pm0.06$ 1
ALBRECHT
1998
ARG ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $9.5 - 10.6$ GeV
$0.54$ $\pm0.28$ $\pm0.14$
ABE
1997O
 SLD 1993--1995 SLC runs
$0.750$ $\pm0.017$ $\pm0.045$ 22k
ALEXANDER
1997F
 CLEO ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $10.6$ GeV
$0.76$ $\pm0.07$ $\pm0.08$ 3230
ALBRECHT
1993G
 ARG ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $9.4 - 10.6$ GeV
$0.734$ $\pm0.055$ $\pm0.027$ 3041
ALBRECHT
1990E
 ARG ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $9.4 - 10.6$ GeV
$0.89$ $\pm0.14$ $\pm0.08$ 1909
FORD
1987B
 MAC ${\it{}E}^{\it{}ee}_{\rm{}cm}$= 29 GeV
$0.81$ $\pm0.13$ 727
BEHRENDS
1985
CLEO ${{\mathit e}^{+}}{{\mathit e}^{-}}$ near ${{\mathit \Upsilon}{(4S)}}$
• • We do not use the following data for averages, fits, limits, etc. • •
$0.747$ $\pm0.048$ $\pm0.044$ 13k
AMMAR
1997B
 CLEO Repl. by ALEXANDER 1997F
$0.693$ $\pm0.057$ $\pm0.028$
BUSKULIC
1995D
 ALEP Repl. by HEISTER 2001E
1  ALBRECHT 1998 use tau pair events of the type ${{\mathit \tau}^{-}}$ ${{\mathit \tau}^{+}}$ $\rightarrow({{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}{{\mathit \nu}_{{{\tau}}}})({{\mathit \pi}^{+}}{{\mathit \pi}^{0}}{{\overline{\mathit \nu}}_{{{\tau}}}}$), and their charged conjugates.
References