LEP EW WG Plots for the big Z-pole Paper
Latest corrections and/or modifications 16-JUN-2005.
You can find here the plots that have been produced for the big
Z-pole paper (summer 2005); for updates including LP05/EPS05 2005
results see here). The Z-pole
measurements from SLD and at LEP-1 are final, while the LEP-2 results
(such as mass and width of the W boson) are still preliminary.
Note that essentially the full set of plots will be made available,
including those that have data that hasn't changed, so that "one-stop
shopping" can be done.
Changes:
Compared to summer 2004 / winter 2005, the final Z-pole heavy-flavour
combination is available, using final measurements and including the
revised correction to go from the measured asymmetry to the pole
asymmetry calculated using the latest ZITTER version 6.41. (Compared
to winter 2005, a small effect in the g/Z interference correction in
Rb and Rc has been fixed, leading to small changes). For the hadronic
vacuum polarisation, the new value of 0.02758+-0.00035 is used for
summer 2005.
Since version 6.40, ZFITTER includes complete two-loop calculations
for MW, leading three-loop rho caluclations, and fermionic two-loop
calculations for sin2teff. For summer 2005, ZFITTER 6.42 is used.
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:
- For plots showing generic SM predictions in form of arrows or areas,
the following parametric variations are used:
dal5had = 0.02758(35) (NEW!),
alpha_s = 0.118(3),
MZ = 91187.5(2.1) MeV,
M_top = 178.0(4.3) 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!
- Afb_q and R_q[=GZ_q/GZ_had] bar-chart plots for heavy quark flavours
comparing ADLOS results:
- In contrast to previous versions of these plots for older
conferences, all numerical values as well as all dots with
error bars are so-called pole quantities, eg, Afb0q, and in
particular corrected to exactly the same set of values for
other parameters. When applicable, the measurements at the
off-peak energy are transported to the peak and included
in the results.
- Thus the results shown are directly comparable, among
themselves as well as with the average, but do not
neccessarily correspond digit-by-digit to the numerical
values found in the individual experimental publications.
- Light-quark effective couplings plot:
- In this analysis, the hadronic Z-decay partial width is no
longer an independent parameter but is calculated as:
GZ_had = GZ_dd+GZ_uu+GZ_ss+GZ_cc+GZ_bb.
- Since there are not sufficiently many different light-quark
flavour pseudo-observables measured to disentangle u, d and s
quarks completely, an assumption is made in the extraction of
pseudo-observables, such as partial widths or effective coupling
constants, for light quarks: quark universality is imposed for
the two down-type light-quark flavours, so that s=d for all
pseudo-observables relating to s and d quarks.
- For the light-quark contours (u and d=s), a second solution
exists, mirroring the contour curves at the origin,
(gvq,gaq) <->(-gvq,-gaq). The light-quark measurements are
also invariant under the exchange gvq<->gaq, leading to
contours symmetric with respect to the diagonal (gvq=gaq).
To resolve these ambiguity, one needs to measure the CM energy
dependence of the asymmetry
(which is done only for the heavy quarks b and c).
- The allowed area for neutrinos, assuming three generations
of neutrinos with identical vector couplings and identical
axial-vector couplings, is bounded by circles centred at the
origin since the invisible partial width constrains the sum
of the squares of the effective couplings only. The ring is
so thin that it appears as a single line in the plot.
- Epsilon-parameter contour
- Based on a fit varying alpha(dal5had), alpha_s, MZ, and the
four epsilon_123b parameters
- Data set consists of all measurements except Gamma_W, M_top
and sin2theta from NUTEV due to its explicit M_top/M_Higgs
dependence (M_top/M_Higgs cannot be expressed in terms of the
four epsilon parameters). APV is also not included, as
additional model assumptions are needed to express APV in
terms of the epsilon parameters.
- STU-parameter contour
- Based on a fit varying alpha(dal5had), alpha_s, MZ, and the
three STgamma_b parameters
- U=0 fixed throughout
- Data set consists of all measurements except Gamma_W, M_top
and sin2theta from NUTEV due to its explicit M_top/M_Higgs
dependence (M_top/M_Higgs cannot be expressed in terms of the
four STUgamma_b parameters). APV is also not included, as
additional model assumptions are needed to express APV in
terms of the STUgamma_b parameters.
- The additional bands correspond to +-1sigma bands for the
alpha_s independent quantities
GZ_lepton, MW and sin2teff (in order of increasing
slope dT/dS). GZ_lepton instead of GZ_tot is chosen because
the latter depends in addition on alpha_s and the former
exhibits a more extreme (ie, flatter) slope.
All other fit parameters are fixed.
- The MSM reference values (STUgamma_b=0) are dal5had=0.02758,
alpha_s=0.118, MZ=91.1875 GeV, M_top=175 GeV, M_Higgs=150 GeV
- 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=178.0+-4.3 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.
- SM parameter sensitivity of each observable
- This normalised sensitivity is calculated as follows:
Within the SM, the partial derivative of the observable calculation
w.r.t. the SM parameter in question is calculated, and then divided
by the measurement error of the observable and multiplied by the
error of the SM parameter. Values and errors for the SM parameters
for this calculation are:
dal5had=0.02758+-0.00035, alpha_s=0.118+-0.003,
MZ=91.1875+-0.0021 GeV, M_top=178.0+-4.3 GeV, M_H=150 GeV and error on
logM_H=0.2.
Enjoy!
Final LEP-1 Z lineshape and leptonic forward-backward asymmetries:
z05_mz.eps
z05_gz.eps
z05_sh.eps
z05_rl.eps
z05_al.eps
z05_rl_afbl_contours.eps
Final LEP-1 tau polarisation:
z05_pt.eps
z05_pe.eps
Final SLD + LEP-1 derived leptonic couplings:
z05_gal_gvl_contours.eps
z05_gll_grl_contours.eps
Final SLD + LEP-1 heavy quark flavours:
afbb_vs_ene.eps
afbc_vs_ene.eps
afbbc_vs_ene.eps
afbb_bar.eps
afbc_bar.eps
afb_all_bb0_final.eps
afb_all_cc0_final.eps
rb_bar.eps
rc_bar.eps
rb_final.eps
rc_final.eps
ab_bar.eps
ac_bar.eps
ac_ab.eps
z05_rb_rc_contours.eps
z05_afbb_afbc_contours.eps
z05_ab_ac_contours.eps
Final SLD + LEP-1 derived couplings:
z05_al_ab_bands.eps
z05_al_ac_bands.eps
z05_gaf_gvf_contours.eps
z05_glf_grf_contours.eps
z05_gab_gvb_contours.eps
z05_glb_grb_contours.eps
z05_gac_gvc_contours.eps
z05_glc_grc_contours.eps
z05_rho_sef_contours.eps
z05_sef2_theta.eps
mw_qqln.eps
mw_qqqq.eps
mw_lep.eps
z05_mw.eps
gw_lep.eps
z05_gw.eps
Preliminary constraints on the Standard Model:
Results from other experiments are also included!
z05_gl_s2_contours.eps
z05_ro_s2_contours.eps
z05_mw_s2_contours.eps
z05_mw_gl_contours.eps
z05_ro_mw_contours.eps
z05_eps_contours.eps
z05_stu_contours.eps
z05_mt_mw_contours.eps
z05_plot_mt.eps
z05_plot_mw.eps
z05_plot_gw.eps
z05_mw_gw_contours.eps
z05_mh_mt_contours.eps
z05_mh_mw_contours.eps
z05_mh_ah_contours.eps
z05_mh_mt_bands.eps
z05_inv_sensitivity_1.eps
z05_top_sensitivity_1.eps
z05_higgs_sensitivity_1.eps
z05_higgs_sensitivity_2.eps
z05_higgs_sensitivity_3.eps
z05_higgs_sensitivity_4.eps
z05_show_ia_sens.eps
z05_show_as_sens.eps
z05_show_mz_sens.eps
z05_show_mt_sens.eps
z05_show_mh_sens.eps
z05_show_higgs.eps
z05_show_pull_18.eps
z05_blueband.eps
Modified: Fri Jul 11 08:14:05 METDST 2003 by Martin Grünewald