Branching Fraction of ${{\boldsymbol Z}^{0}}$ to a Pair of Stable Charged Heavy Fermions INSPIRE search

VALUE CL% DOCUMENT ID TECN  COMMENT
• • • We do not use the following data for averages, fits, limits, etc. • • •
$<5 \times 10^{-6}$ 95 1
 1995 R
OPAL $\mathit m$= $40.4 - 45.6$ GeV
$<1 \times 10^{-3}$ 95
 1990 O
OPAL $\mathit m$ = 29$-$40 GeV
1  AKERS 1995R give the 95$\%$ CL limit $\sigma\mathrm {( {{\mathit X}} {{\overline{\mathit X}}} )}/\sigma\mathrm {( {{\mathit \mu}} {{\mathit \mu}} )}$ $<1.8 \times 10^{-4}$ for the pair production of singly- or doubly-charged stable particles. The limit applies for the mass range $40.4 - 45.6$ GeV for ${{\mathit X}^{\pm}}$ and $<45.6$ GeV for ${{\mathit X}^{\pm\pm}}$. See the paper for bounds for $\mathit Q$ = $\pm2$/3, $\pm4$/3.
References:
 AKERS 1995R
ZPHY C67 203 Search for Heavy Charged Particles and for Particles with Anomalous Charge in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Collisions at LEP
 AKRAWY 1990O
PL B252 290 Search for Pair Produced Stable Singly-Charged Heavy Particles in ${{\mathit Z}^{0}}$ Decays