(${\mathit m}_{{{\mathit \tau}^{+}}}–{\mathit m}_{{{\mathit \tau}^{-}}})/\mathit m_{{\mathrm {average}}}$

INSPIRE  
A test of $\mathit CPT$ invariance.
VALUE CL% DOCUMENT ID TECN  COMMENT
$\bf{<2.8 \times 10^{-4}}$ 90
BELOUS
2007
BELL 414 fb${}^{-1}$, ${\it{}E}^{\it{}ee}_{\rm{}cm}$=10.6 GeV
• • We do not use the following data for averages, fits, limits, etc. • •
$<5.5 \times 10^{-4}$ 90 1
AUBERT
2009AK
 BABR 423 fb${}^{-1}$, ${\it{}E}^{\it{}ee}_{\rm{}cm}$=10.6 GeV
$<3.0 \times 10^{-3}$ 90
ABBIENDI
2000A
 OPAL $1990 - 1995$ LEP runs
1  AUBERT 2009AK quote both the listed upper limit and (${\mathit m}_{{{\mathit \tau}^{+}}}–{\mathit m}_{{{\mathit \tau}^{-}}})/\mathit m_{{\mathrm {average}}}$ = ($-3.4$ $\pm1.3$ $\pm0.3$) $ \times 10^{-4}$.
Conservation Laws:
$\mathit CPT$ INVARIANCE
References:
AUBERT 2009AK
PR D80 092005 Measurements of the ${{\mathit \tau}}$ Mass and the Mass Difference of the ${{\mathit \tau}^{+}}$ and ${{\mathit \tau}^{-}}$ at BABAR
BELOUS 2007
PRL 99 011801 Measurement of the ${{\mathit \tau}}$ Lepton Mass and an Upper Limit on the Mass Difference between ${{\mathit \tau}^{+}}$ and ${{\mathit \tau}^{-}}$
ABBIENDI 2000A
PL B492 23 A Measurement of the ${{\mathit \tau}}$ Mass and First $\mathit CPT$ Test with ${{\mathit \tau}}$ Leptons