Apel, W.D.
E+ E- --> E- E+
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Improved measurements of cross-sections and asymmetries at the Z0 resonance

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Nucl.Phys.B 418 (1994) 403-427, 1994.
Inspire Record 373114 DOI 10.17182/hepdata.48349

During the 1992 running period of the LEP e + e − collider, the DELPHI experiment accumulated approximately 24 pb − of data at the Z 0 peak. The decays into hadrons and charged leptons have been analysed to give values for the cross sections and leptonic forward-backward asymmetries which are significantly improved with respect to those previously published by the DELPHI collaboration. Incorporating these new data, more precise values for the Z 0 resonance parameters are obtained from model-independent fits. The results are interpreted within the framework of the Standard Model, yielding for the top quark mass m t = 157 −48 +36 (expt.) −20 +19 (Higgs) GeV, and for the effective mixing angle sin 2 θ eff lept = 0.2328 ± 0.0013 (expt.) −0.0003 +0.0001 (Higgs), where (Higgs) represents the variation due to Higgs boson mass in the range 60 to 1000 GeV, with central value 300 GeV.

10 data tables
Table 1

No description provided.

Table 2

First result corresponds to the total cross section (i.e. S+T channel), while second one corresponds to S-channel only. An acollinearity less that 10 deg.

Table 3

Forward-backward asymmetry within the polar angular range 44 < THETA < 136 degrees and acollinearity < 10 degrees.. First result corresponds to the total cross section (i.e. S+T channel), while second one corresponds to S-channel only.

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Electroweak Effects in $e^+ e^- \to e^+ e^-$ at $\sqrt{s}=29$-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.D 35 (1987) 10-18, 1987.
Inspire Record 230164 DOI 10.17182/hepdata.3835

A high-precision measurement of the differential cross section for Bhabha scattering (e+e−→e+e−) is presented. The measurement was performed with the MAC detector at the PEP storage ring of the Stanford Linear Accelerator Center, at a center-of-mass energy of 29 GeV. Effects due to electroweak interference are observed and agree well with the predictions of the Glashow-Salam-Weinberg model. The agreement between the data and the electroweak prediction rules out substructure of the electron up to mass scales of 1 TeV.

5 data tables
Table 1

Error contains both statistics and systematics.

Table 2

No description provided.

Table 3

No description provided.

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On the Model Dependence of the Determination of the Strong Coupling Constant in Second Order {QCD} From $e^+ e^-$ Annihilation Into Hadrons

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.
Phys.Lett.B 138 (1984) 311-316, 1984.
Inspire Record 195332 DOI 10.17182/hepdata.6634

Hadronic events obtained with the CELLO detector at PETRA are compared with second order QCD predictions using different models for the fragmentation of quarks and gluons into hadrons. We find that the model dependence in the determination of the strong coupling constant persists when going from first to second order QCD calculations.

3 data tables
Table 1

ASYMMETRY FOR DATA CORRECTED WITH IF MODEL (ALPHA-S=0.12).

Table 2

ASSYMETRY FOR DATA CORRECTED WITH SF MODEL (ALPHA-S=0.19).

Table 3

No description provided.