LEP EW WG Plots for the Summer 2006
Latest corrections and/or modifications 11-September-2006.
You can find here the plots that have been updated for the Summer
2006 conferences. Most results are final, such as the Z-pole
measurements from SLD and at LEP. The LEP-2 results (such as
mass and width of the W boson) are still
preliminary.
Changes:
Compared to the final Z-pole paper,
the updates are:
- mass of the top quark from the Tevatron (updated for summer 2006: final Run-I and preliminary Run-II results)
- width of the W boson from the Tevatron (updated already for winter 2006)
- mass and width of the W boson from LEP-2 (updated for summer 2006: final
results from Aleph, Delphi, L3, Opal, but preliminary combination)
As before, version 6.42 of ZFITTER is used for SM calculations.
Attention:
Since winter 2004, the global SM fits now use only
high-Q2 results from LEP, SLC and the Tevatron (together with the
hadronic vacuum polarisation). This disentangles the numerical
Higgs-mass constraint and limit from the issue of the high chi2 caused
by the low-Q2 NuTeV measurement which, however, has only a small
influence on the fitted Higgs mass. Based on these high-Q2 analyses,
predictions for low-Q2 measurements such as atomic parity violation in
cesium (APV), parity violation in Moller scattering (e-e-), and
neutrino-nucleon scattering (NuTeV) are derived.
Answers to FAQs on plots presented below:
- Only updated plots are collected on this page.
- While the measurements of W mass and W width of all four LEP
experiments are now final and used in the combination, the LEP
combination itself is still preliminary as it uses a preliminary LEP-2
combined estimate for the effect of color reconnection.
- For plots showing generic SM predictions in form of arrows or areas,
the following parametric variations are used:
dal5had = 0.02758(35),
alpha_s = 0.118(3),
MZ = 91187.5(2.1) MeV,
M_top = 171.4(2.1) GeV,
M_Higgs = 300+700-186 GeV (lower limit of 114 GeV as given by the
direct search). The arrows are pointing in the
direction of increasing parameter values!
- Higgs constraint from each measurement:
- For each observable, the corresponding constraint on the
Higgs mass is determined in a full MSM fit to the measurement
result of this observable, constraining
dal5had=0.02758+-0.00035, alpha_s=0.118+-0.003, MZ =
91.1875+-0.0021 GeV and M_top=171.4+-2.1 GeV.
- For Higgs masses larger than about 1 TeV, the MSM and its
formulae used do not make too much sense, so that part of
the Higgs mass regime is cut of as it should not be taken
quantitatively.
- The vertical green band denotes the overall constraint on the
Higgs mass derived from the fit to all data.
- The vertical black line denotes the limit on the Higgs mass
obtained from the direct search at LEP-2.
- The effects of real Higgs-strahlung, Z*+H, is not taken into
account, neither in the experimental analyses (such as
Higgs-mass dependent efficiencies for various Z*H decay
channels) nor in the calculation of MSM predictions (increased
Z decay widths). Thus quantitative conclusions from individual
observables are uncertain in the low Higgs-mass regime.
Enjoy!
Preliminary LEP-2 W mass and width:
mw_qqln.eps
mw_qqqq.eps
mw_ffff.eps
s06_mw.eps
gw_ffff.eps
s06_gw.eps
Preliminary constraints on the Standard Model:
Results from other experiments are also included!
s06_plot_mt.eps
s06_plot_mw.eps
s06_plot_gw.eps
s06_stu_contours.eps
s06_gl_s2_contours.eps
s06_mh_mt_contours.eps
s06_mh_mw_contours.eps
s06_mt_mw_contours.eps
s06_show_higgs.eps
s06_show_pull_18.eps
s06_blueband.eps
Modified: Sat Mar 18 11:54:05 METDST 2006 by Martin Grünewald