#### ${{\mathit Z}}$ WIDTH

OUR FIT is obtained using the fit procedure and correlations as determined by the LEP Electroweak Working Group (see the note “The ${{\mathit Z}}$ boson” and ref. LEP-SLC 2006 ).
VALUE (GeV) EVTS DOCUMENT ID TECN  COMMENT
 $\bf{ 2.4952 \pm0.0023}$ OUR FIT
$2.4948$ $\pm0.0041$ 4.57M 1
 2001 A
OPAL ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $88 - 94$ GeV
$2.4876$ $\pm0.0041$ 4.08M 2
 2000 F
DLPH ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $88 - 94$ GeV
$2.5024$ $\pm0.0042$ 3.96M 3
 2000 C
L3 ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $88 - 94$ GeV
$2.4951$ $\pm0.0043$ 4.57M 4
 2000 C
ALEP ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $88 - 94$ GeV
• • We do not use the following data for averages, fits, limits, etc. • •
$2.4943$ $\pm0.0041$ 5
 2004 G
OPAL ${\it{}E}^{\it{}ee}_{\rm{}cm}$= LEP1 + $130 - 209$ GeV
$2.5025$ $\pm0.0041$ 3.97M 6
 2000 Q
L3 ${\it{}E}^{\it{}ee}_{\rm{}cm}$= LEP1 + $130 - 189$ GeV
$2.50$ $\pm0.21$ $\pm0.06$ 7
 1996 R
DLPH ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $91.2$ GeV
$3.8$ $\pm0.8$ $\pm1.0$ 188
 1989 C
CDF ${\it{}E}^{\it{}p\overline{\it{}p}}_{\rm{}cm}$= $1.8$ TeV
$2.42$ ${}^{+0.45}_{-0.35}$ 480 8
 1989 B
MRK2 ${\it{}E}^{\it{}ee}_{\rm{}cm}$= $89 - 93$ GeV
$2.7$ ${}^{+1.2}_{-1.0}$ $\pm1.3$ 24 9
 1989
UA1 ${\it{}E}^{\it{}p\overline{\it{}p}}_{\rm{}cm}$= 546,630 GeV
$2.7$ $\pm2.0$ $\pm1.0$ 25 10
 1987
UA2 ${\it{}E}^{\it{}p\overline{\it{}p}}_{\rm{}cm}$= 546,630 GeV
 1 ABBIENDI 2001A error includes approximately $3.6$ MeV due to statistics, 1$~$MeV due to event selection systematics, and $1.3$ MeV due to LEP energy uncertainty.
 2 The error includes $1.2$ MeV due to LEP energy uncertainty.
 3 The error includes $1.3$ MeV due to LEP energy uncertainty.
 4 BARATE 2000C error includes approximately $3.8$ MeV due to statistics, $0.9~$MeV due to experimental systematics, and $1.3~$MeV due to LEP energy uncertainty.
 5 ABBIENDI 2004G obtain this result using the S$-$matrix formalism for a combined fit to their cross section and asymmetry data at the ${{\mathit Z}}$ peak and their data at $130 - 209$ GeV. The authors have corrected the measurement for the 1 MeV shift with respect to the Breit$-$Wigner fits.
 6 ACCIARRI 2000Q interpret the $\mathit s$-dependence of the cross sections and lepton forward-backward asymmetries in the framework of the S-matrix formalism. They fit to their cross section and asymmetry data at high energies, using the results of S-matrix fits to ${{\mathit Z}}$ -peak data (ACCIARRI 2000C) as constraints. The $130 - 189$ GeV data constrains the ${{\mathit \gamma}}$ /${{\mathit Z}}$ interference term. The authors have corrected the measurement for the $0.9$ MeV shift with respect to the Breit-Wigner fits.
 7 ABREU 1996R obtain this value from a study of the interference between initial and final state radiation in the process ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ .
 8 ABRAMS 1989B uncertainty includes 50 MeV due to the miniSAM background subtraction error.
 9 ALBAJAR 1989 result is from a total sample of 33 ${{\mathit Z}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ events.
 10 Quoted values of ANSARI 1987 are from direct fit. Ratio of ${{\mathit Z}}$ and ${{\mathit W}}$ production gives either $\Gamma\mathrm {({{\mathit Z}} )}$ $<$ ($1.09$ $\pm0.07$) ${\times }$ $\Gamma\mathrm {({{\mathit W}} )}$, CL = 90$\%$ or $\Gamma\mathrm {({{\mathit Z}} )}$ = ($0.82$ ${}^{+0.19}_{-0.14}$ $\pm0.06$) ${\times }$ $\Gamma\mathrm {({{\mathit W}} )}$. Assuming Standard-Model value $\Gamma\mathrm {({{\mathit W}} )}$ = 2.65 GeV then gives $\Gamma\mathrm {({{\mathit Z}} )}$ $<$ $2.89$ $\pm0.19$ or = $2.17$ ${}^{+0.50}_{-0.37}$ $\pm0.16$.
References:
 ABBIENDI 2004G
EPJ C33 173 Tests of the Standard Model and Constraints on New Physics from Measurements of Fermion Pair Production at 189 to 209 GeV at LEP
 ABBIENDI 2001A
EPJ C19 587 Precise Determination of the ${{\mathit Z}}$ Resonance Parameters at LEP: “Zedometry''
 ABREU 2000F
EPJ C16 371 Cross Sections and Leptonic Forward-Backward Asymmetries from the ${{\mathit Z}^{0}}$ Running of LEP
 ACCIARRI 2000C
EPJ C16 1 Measurements of Cross Sections and Forward Backward Asymmetries at the ${{\mathit Z}}$ Resonance and Determination of Electroweak Parameters
 ACCIARRI 2000Q
PL B489 93 Determination of ${{\mathit \gamma}}$ /${{\mathit Z}}$ Interference in ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ Annihilation at LEP
 BARATE 2000C
EPJ C14 1 Measurement of the ${{\mathit Z}}$ Resonance Parameters at LEP
 ABREU 1996R
ZPHY C72 31 First Study of the Interference between Initial and Final State Radiation at the ${{\mathit Z}}$ Resonance
 ABE 1989C
PRL 63 720 Measurement of the Mass and Width of ${{\mathit Z}^{0}}$ Boson at the Fermilab Tevatron
 ABRAMS 1989B
PRL 63 2173 Measurements of ${{\mathit Z}^{0}}$ -Boson Resonance Parameters in ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ Annihilation
 ALBAJAR 1989
ZPHY C44 15 Studies of Intermediate Vector Boson Production and Decay in UA1 at the CERN Proton-Antiproton Collider
 ANSARI 1987
PL B186 440 Measurement of the Standard Model Parameters from a Study of ${{\mathit W}}$ and ${{\mathit Z}^{0}}$ Bosons