Observation of a Charge Asymmetry in $e^+ e^- \to \mu^+ \mu^-$

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 108 (1982) 140-144, 1982.
Inspire Record 168234 DOI 10.17182/hepdata.31023

The angular distribution and the s dependence of the total cross section for the process e + e − → μ + μ − have been measured using the JADE detector at PETRA. After radiative corrections, a forward-backward asymmetry of −(11.8±3.8) % was observed at an average centre of mass energy of 33.5 GeV. For comparison, an asymmetry of −7.8 % is expected on the basis of the standard Glashow-Salam-Weinberg model.

5 data tables

Best fit to total cross section in energy range.

ANGULAR DISTRIBUTION.

Forward-backward asymmetry within the acceptnce region.

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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”.

6 data tables

QED comparison is to point like cross section.

Angular distributions - data requested from authors.

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.

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