Tau Lepton Production and Decay at {PETRA} Energies

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Phys.Lett.B 161 (1985) 188, 1985.
Inspire Record 220695 DOI 10.17182/hepdata.30350

The production and decay of τ-pairs was studied with the JADE detector at PETRA at center-of-mass energies of 30 ⩽√ s ⩽ 46.78 GeV. The total production cross section for τ-pairs agreed with QED predictions to order α 3 . Lower limits on QED cut-off parameters of Λ + > 285 GeV and Λ − > 210 GeV at 95% confidence level were ontained. The decay branching fractions into one and three charged particles were determined to be (86.1 ± 0.5 ± 0.9)% and (13.6±0.5 ±0.80)%. In the angular distributions a forward-backward asymmetry was observed, from which the axial-vector weak charge to the τ was determined to be a τ = −0.74 ± 0.22 in agreement with the standard model. An analysis of the process e + e − → τ + τ − γ showed agreement with QED calculations to O(α 3 ).

2 data tables match query

Forward-backward asymmetry determined from fit to angular distribution of form N*(1 + cos(theta)**2 + (3/8)*A*cos(theta)).

Study of radiative tau events.


New Results on $e^+ e^- \to \mu^+ \mu^-$ From the Jade Detector at {PETRA}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Z.Phys.C 26 (1985) 507, 1985.
Inspire Record 204492 DOI 10.17182/hepdata.16141

The production of collinear muon pairs has been studied using the JADE detector at thee+e− storage ring at PETRA. Results for the total cross section and the angular distribution were obtained at centre of mass (cm) energies ranging from 12 to 46 GeV. The data correspond to an integrated luminosity offLdt>90 pb−1, of which 71.2 pb−1 were taken at\(\left\langle {\sqrt s } \right\rangle \)=34.4 GeV and 17 pb−1 at\(\left\langle {\sqrt s } \right\rangle \)=42.4 GeV. The results are compared to electroweak theories, in particular the “Standard Model”.

2 data tables match query

Forward-backward asymmetry calculated from a fit to the angular distribution of the form 1: + cos(theta)**2 + Bcos(theta).. Asymmetries quoted here are extrapolated to full solid angle. The asymmetry at sqrt(s) = 34.4 is -11.10 +- 1.75 +- 1.0 pct if the end-cap points are included.

No description provided.


Tests of the Standard Model in Leptonic Reactions at {PETRA} Energies

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Z.Phys.C 30 (1986) 371, 1986.
Inspire Record 222566 DOI 10.17182/hepdata.48419

An analysis of the three leptonic reactionse+e−→e+e−,μ+μ− andτ+τ− over a wide range of energy,\(12< \sqrt s< 46.78 GeV\) is presented. The data were obtained with the JADE detector at thee+e− storage ring PETRA. They are compared to predictions of electroweak theories, in particular the standard model. For the total cross-sections of all three reactions and for the differential cross-section of Bhabha scattering no deviation from QED is found over the entire energy range. The differential cross-sections of μ and τ pairs at high energies show the angular asymmetry predicted by electroweak interference. The axial-vector and vector weak coupling constant, sin2θW andMZ are determined and compared to other measurements. Finally, limits on deviations from the standard model are given.

6 data tables match query

Forward-Backward Asymmetry measurements.

Forward-Backward Asymmetry measurements.

No description provided.

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A Measurement of the Weak Axial Couplings of the $b$ and $c$ Quark

The JADE collaboration Elsen, E. ; Allison, J. ; Ambrus, K. ; et al.
Z.Phys.C 46 (1990) 349-360, 1990.
Inspire Record 282535 DOI 10.17182/hepdata.15241

The forward-backward charge asymmetries of theb andc quarks are measured with the JADE detector at PETRA at\(\sqrt s= 35\) GeV and 44 GeV using both electrons and muons to tag the heavy quarks. At\(\sqrt s= 35\) GeV, a simultaneous fit for the two asymmetries yields the resultAb=−9.3±5.2% (state.) ndAc=−9.6±4.0% (stat.). The systematic errors are comparable with the statistical uncertainties. Combining the measurements at both energies and alternately constraining the weak coupling of thec andb quark to their Standard Model values (ac=1,ab=−1) increases the precision of the measurement of coupling constant of the other quark. Using this procedureab=−0.72±0.34 andac=0.79±0.40, where the numbers are corrected for\(B\bar B - mixing\) and the errors include both statistical and systematic contributions. The mixing parameter for continuum\(b\bar b - production\) is determined to be χ-0.24±0.12 if both heavy quark coupling constants are constrained to their values in the Standard Model.

4 data tables match query

Results of simultaneous fit to both asymmetries. This table is for the CHARMED quark.

Results of simultaneous fit to both asymmetries. This table is for the BOTTOM quark.

Results for BOTTOM quark asymmetry with c asymmetry constrained to the standard model value.

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