${{\boldsymbol \mu}}$ DECAY PARAMETERS
($\mathit V−\mathit A$) theory predicts $\rho $ = 0.75.
| $\bf{
0.74979 \pm0.00026}$
|
OUR AVERAGE
|
| $0.74977$ $\pm0.00012$ $\pm0.00023$ |
|
1 |
|
TWST |
+ |
| $0.7518$ $\pm0.0026$ |
|
|
|
RVUE |
|
| • • • We do not use the following data for averages, fits, limits, etc. • • • |
| $0.75014$ $\pm0.00017$ $\pm0.00045$ |
|
2 |
|
TWST |
+ |
| $0.75080$ $\pm0.00032$ $\pm0.00100$ |
6G |
3 |
|
TWST |
+ |
| $0.72$ $\pm0.06$ $\pm0.08$ |
|
|
|
ICAR |
|
| $0.762$ $\pm0.008$ |
170k |
4 |
|
ASPK |
+ |
| $0.760$ $\pm0.009$ |
280k |
4 |
|
ASPK |
+ |
| $0.7503$ $\pm0.0026$ |
800k |
4 |
|
ASPK |
+ |
|
1
The quoted systematic error includes a contribution of 0.00013 (added in quadrature) from uncertainties on radiative corrections and on the Michel parameter $\eta $.
|
|
2
The quoted systematic error includes a contribution of 0.00011 (added in quadrature) from the dependence on the Michel parameter $\eta $.
|
|
3
The quoted systematic error includes a contribution of $0.00023$ (added in quadrature) from the dependence on the Michel parameter $\eta $.
|
|
4
${{\mathit \eta}}$ constrained = 0. These values incorporated into a two parameter fit to ${{\mathit \rho}}$ and ${{\mathit \eta}}$ by DERENZO 1969 .
|
|
| References: |
|
| PRL 106 041804 |
Experimental Constraints on Left-Right Symmetric Models from Muon Decay |
|
| PR D78 032010 |
Precision Measurement of the Muon Decay Parameters ${{\mathit \rho}}$ and ${{\mathit \delta}}$ |
|
| PRL 94 101805 |
Measurement of the Michel Parameter ${{\mathit \rho}}$ in Muon Decay |
|
| EPJ C33 233 |
Measurement of the ${{\mathit \mu}}$ Decay Spectrum with the ICARUS Liquid Argon TPC |
|
| PR 181 1854 |
Measurement of the Low Energy End of the ${{\mathit \mu}^{+}}$ Decay Spectrum |
|
| PR 166 1379 |
Measurement of the Muon Decay Spectrum with a Wire Spark Chamber Spectrometer |
|
| PR 156 1475 |
Measurement of the Muon Decay Spectrum with a Wire Spark Chamber Spectrometer |
|
| Nevis 147 unpub. |
Positron Spectrum from Muon Decay. |
|
