HEPData Search

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Measurement of the Processes $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at {PETRA}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.

Z.Phys.C 19 (1983) 197, 1983.

Inspire Record 191231 DOI 10.17182/hepdata.45206

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies$\sqrt s $ between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy,$\left\langle {\sqrt s } \right\rangle= 34.6 GeV$, the 1 δ limits 0.12<sin2 ϑw<0.38 are obtained for the weak mixing angle. The higher order (α3) QED processese+e−→e+e−γ ande+e−→γγγ are also studied and are found to agree with the α3 QED predictions. A search for excited electrons is carried out by investigating the (e±γ) invariant mass distribution in the reactione+e−→e+e−γ.

2 data tables match query

Table 2

Angular distribution.

Table 3

Angular distribution.

Search for Narrow Resonances in $e^+ e^-$ Annihilation at $c$.m. Energies Between 33.0-{GeV} and 36.72-{GeV}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.

Phys.Lett.B 100 (1981) 364-366, 1981.

Inspire Record 164319 DOI 10.17182/hepdata.45224

A search for narrow resonances in e + e − annihilation between 33.00 and 36.72 GeV is reported. No evidence is found for the existence of such states. The 90% confidence upper limit on the integrated resonance cross section is determined to be 28 nb MeV, a value significantly below that expected for the lowest t t bound state.

2 data tables match query

Table 1

AVERAGE R VALUE THROUGHOUT ENERGY RANGE. SYSTEMATIC ERROR IS CONSERVATIVE AND WILL BE IMPROVED.

Table 2

R VALUES AT 20 MEV STEPS. DATA TAKEN FROM TABLE IN THE PREPRINT.

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

Table 1

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

Table 2

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

Table 3

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

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Final Results on $\mu$ and Tau Pair Production by the Jade Collaboration at {PETRA}

The JADE collaboration Hegner, S. ; Naroska, B. ; Schroth, F. ; et al.

Z.Phys.C 46 (1990) 547-554, 1990.

Inspire Record 284560 DOI 10.17182/hepdata.15279

The cross-sections and the forward-backward charge asymmetries of muon and tau pairs produced ine+e− collisions at$\sqrt s= 35 GeV$ have been measured by the JADE Collaboration. The cross-sections,$\sigma _\mu(\sqrt s= GeV) = 69.79 \pm 1.35 \pm 1.40 pb$ and$\sigma _\mu(\sqrt s= GeV) = 71.72 \pm 1.48 \pm 1.61 pb$, are in agreement with the QED α3 prediction. The charge asymmetries areAμ=−(9.9±1.5±0.5)% andAτ=−(8.1±2.0±0.6)% in agreement with the value −9.2% predicted by the standard model, usingMZ=91.0 GeV and sin2θW=0.230.

2 data tables match query

Table 1

No description provided.

Table 2

No description provided.

A Measurement of the Charmed Quark Asymmetry in $e^+ e^-$ Annihilation

The JADE collaboration Ould-Saada, F. ; Allison, J. ; Ambrus, K. ; et al.

Z.Phys.C 44 (1989) 567, 1989.

Inspire Record 278937 DOI 10.17182/hepdata.15357

The charmed quark charge asymmetry has been measured at the average centre of mass energy of 35 GeV with the JADE detector at thee+e− storage ring PETRA. Charmed quarks were identified byD*± tagging using the ΔM technique.D*± mesons were reconstructed through their decay intoD0 mesons resulting in (Kπ) π and (K π π π) π final states. The measured charge asymmetryA=−0.149±0.067 is in agreement with the expectation from the electroweak interference effect in quantum flavour dynamics (QFD).

1 data table match query

Table 1

CHARMED quark charge asymmetry.

rivet Analysis
A Study of Photon Production in Hadronic Events from e+ e- Annihilation

The JADE collaboration Pitzl, D.D. ; Allison, J. ; Ambrus, K. ; et al.

Z.Phys.C 46 (1990) 1-7, 1990.

Inspire Record 282847 DOI 10.17182/hepdata.15300

Results are presented on an investigation of photons produced in multihadronic final states frome+e− annihilation at 35 GeV and 44 GeV center of mass energies. Scalling violation between 14 and 44 GeV is observed in inclusive photon spectra. Comparing inclusive π0 spectra with charged pion spectra it is found that the average π0 multiplicity exceeds the charged pion multiplicity scaled by factor of 0.5 by (16±5)% and (21±7)% at 35 and 44 GeV respectively. The excess can be attributed to isospin violating decays of hadrons. The η multiplicity is found to be 〈nη〈=0.64±0.09±0.06 at 35 GeV. With a significance of three standard deviations a signal from quark bremsstrahlung is observed. The measured charge asymmetry in hadronic final states, due to the interference between initial and final state radiation, ofA=−0.141±0.041 is in accord with QED expectations. An interference effect in the azimuth angle distribution of charged jets around the photon direction is observed for the first time.

7 data tables match query

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Charged Particle and Neutral Kaon Production in e+ e- Annihilation at PETRA

The JADE collaboration Bartel, W. ; Becker, L. ; Bawbery, C. ; et al.

Z.Phys.C 20 (1983) 187, 1983.

Inspire Record 190818 DOI 10.17182/hepdata.16288

None

3 data tables match query

Table 1

MEAN CHARGED MULTIPLICITY.

Table 2

MEAN CHARGED MULTIPLICITY AFTER SUBTRACTING SECONDARIES FROM KS AND LAMBDA DECAY, PLUS LEPTONS FROM HEAVY QUARK WEAK DECAYS ARE FROM DALITZ DECAYS. I.E. NUMBER OF CHARGED HADRONS HAVING LIFETIME > 10**-9 SEC.

Table 3

INVERSE RELATIVE DISPERSION.

rivet Analysis
Measurements of Energy Correlations in $e^+ e^- \to$ Hadrons

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.

Z.Phys.C 25 (1984) 231, 1984.

Inspire Record 202784 DOI 10.17182/hepdata.1998

Energy-energy-correlations (EEC) have been measured with the JADE detector at c.m. energies of 14 GeV, 22 GeV and in the region 29 GeV<Ecm<36 GeV. Corrected results are presented of EEC and their asymmetry, which can be directly compared to theoretical predictions. At 〈Ecm〉=34 GeV a comparison with second order QCD predictions yields good agreement for the string model fragmentation resulting in a value of the strong coupling constant αs=0.165±0.01 (stat.). The independent fragmentation models, which yield values of αs between 0.10 and 0.15 depending on the treatment of energy and momentum conservation and of the gluon splitting, do not provide a satisfactory description of the data over the full angular range.

3 data tables match query

Table 1

TABLES GIVEN HERE CONTAIN SELF CORRELATION. THIS IS SUBTRACTED IN THE FIGURE.

Table 2

VALUE OF ASSYMETRY IN CORRELATIONS.

Table 3

No description provided.

A Measurement of the Electroweak Induced Charge Asymmetry in e+ e- ---> B anti-B

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.

Phys.Lett.B 146 (1984) 437-442, 1984.

Inspire Record 203144 DOI 10.17182/hepdata.6565

The forward-backward charge asymmetry for the process e + e − → b b ̄ → μ ± + hadrons has been measured using the JADE detector at PETRA. An asymmetry of (−22.8 ± 6.0 ± 2.5)% was observed at an average center of mass energy of 34.6 GeV. For comparison, an asymmetry of −25.2% is expected on the basis of the standard Glashow-Salam-Weinberg model.

4 data tables match query

Table 1

THE VALUE OF CONST HAVE BEEN RESCALED TO DEFINITION I3(Q) = 1/2 BY OPY.

Table 2

No description provided.

Table 3

No description provided.

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