QCD analyses and determinations of alpha(s) in e+ e- annihilation at energies between 35-GeV and 189-GeV.

The JADE & OPAL collaborations Pfeifenschneider, P. ; Biebel, O. ; Movilla Fernandez, P.A. ; et al.
Eur.Phys.J.C 17 (2000) 19-51, 2000.
Inspire Record 513337 DOI 10.17182/hepdata.12882

We employ data taken by the JADE and OPAL experiments for an integrated QCD study in hadronic e+e- annihilations at c.m.s. energies ranging from 35 GeV through 189 GeV. The study is based on jet-multiplicity related observables. The observables are obtained to high jet resolution scales with the JADE, Durham, Cambridge and cone jet finders, and compared with the predictions of various QCD and Monte Carlo models. The strong coupling strength, alpha_s, is determined at each energy by fits of O(alpha_s^2) calculations, as well as matched O(alpha_s^2) and NLLA predictions, to the data. Matching schemes are compared, and the dependence of the results on the choice of the renormalization scale is investigated. The combination of the results using matched predictions gives alpha_s(MZ)=0.1187+{0.0034}-{0.0019}. The strong coupling is also obtained, at lower precision, from O(alpha_s^2) fits of the c.m.s. energy evolution of some of the observables. A qualitative comparison is made between the data and a recent MLLA prediction for mean jet multiplicities.

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Overall result for ALPHAS at the Z0 mass from the combination of the ln R-matching results from the observables evolved using a three-loop running expression. The errors shown are total errors and contain all the statistics and systematics.

Weighted mean for ALPHAS at the Z0 mass determined from the energy evolutions of the mean values of the 2-jet cross sections obtained with the JADE and DURHAMschemes and the 3-jet fraction for the JADE, DURHAM and CAMBRIDGE schemes evaluted at a fixed YCUT.. The errors shown are total errors and contain all the statistics and systematics.

Combined results for ALPHA_S from fits of matched predicitions. The first systematic (DSYS) error is the experimental systematic, the second DSYS error isthe hadronization systematic and the third is the QCD scale error. The values of ALPHAS evolved to the Z0 mass using a three-loop evolution are also given.

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Precise Measurement of Total Cross-Sections for the Process e+ e- ---> Multi-Hadrons in the Center-Of-Mass Energy Range Between 12.0-GeV and 36.4-GeV

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 129 (1983) 145-152, 1983.
Inspire Record 191159 DOI 10.17182/hepdata.6639

The total cross section for the process e + e − → hadrons has been measured in the CM energy range between 12.0 and 36.4 GeV using the JADE detector with a typical systematic error of ±3%. The ratio R( σ( ee → hadrons ) σ pt ) is found to be constant over this range with an average value of 3.97 ± 0.05 (statistical and point-to-point systematic error) ± 0.10 (normalization error). The data were compared with the standard electro-weak interaction model including QCD corrections.

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ERRORS ARE STATISTICAL PLUS POINT TO POINT SYSTEMATICS. THERE IS AN ADDITIONAL 2.4 PCT OVERALL NORMALIZATION ERROR.

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Experimental Investigation of the Energy Dependence of the Strong Coupling Strength

The JADE collaboration Bethke, S. ; Allison, John ; Ambrus, K. ; et al.
Phys.Lett.B 213 (1988) 235-241, 1988.
Inspire Record 263579 DOI 10.17182/hepdata.29894

The energy dependence of the relative production rate of three-jet events is studied in hadronic e + e − annihilation events at center of mass energies between 22 and 46.7 GeV. Three-jet events are defined by a jet finding algorithm which is closely related to the definition of resolvable jets used in O( α s 2 ) perturbative QCD calculations, where the relative production rate of three-jet events is roughly proportional to the size of the strong coupling strength. The production rates of three-jet events in the data decrease significantly with increasing centre of mass energy. The experimental rates, which are independent of fragmentation model calculations, can be directly compared to theoretically calculated jet production rates and are in good agreement with the QCD expectations of a running coupling strength. The hypothesis of an energy independent coupling constant can be excluded with a significance of four standard derivations.

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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.

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Best fit to total cross section in energy range.

ANGULAR DISTRIBUTION.

Forward-backward asymmetry within the acceptnce region.

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Baryon Production in e+ e- Annihilation at PETRA

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 104 (1981) 325-329, 1981.
Inspire Record 166363 DOI 10.17182/hepdata.31062

Data on p and Λ production by e + e − -annihilation at CM energies between 30 and 36 GeV are presented. Indication for an angular anticorrelation in events with baryon-antibaryon pairs is seen.

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AVERAGE NUMBER OF ANTIBARYONS PER HADRONIC EVENT. AN EXPONENTIAL SLOPE OF 2.5 GEV*-1 IN E WAS ASSUMED IN EXTRAPOLATING E*D3(SIG)/DP**3 TO ALL MOMENTA.


A Determination of Quark Weak Couplings at {PETRA} Energies

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 101 (1981) 361, 1981.
Inspire Record 164812 DOI 10.17182/hepdata.31227

Data on hadron production by e + e − annihilation at c.m. energies between 12 and 36.6 GeV have been collected using the JADE detector. They have been analysed in terms of single-photon and weak neutral-current exchange assuming production of quark-antiquark pairs with only d, u, s, c and b quarks to produce values for the quark weak neutral-current couplings. A further analysis in terms of the Glashow-Salam-Weinberg theory produced the result, sin 2 θ W = 0.22 ± 0.08 . The theory has therefore been tested in a new energy domain and within the context of the neutral weak couplings of the first, second and third generation quarks.

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WIDTH(Z) = 2.5 GEV WAS ASSUMED. CONST(N=SIN2TW) WAS DETERMINED FROM RATIO(HADRONS/MU). FIRST ORDER QCD.


Observation of Inclusive $\eta$ Production in $e^+ e^-$ Annihilation at {CM} Energies of 34-{GeV}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 130 (1983) 454-458, 1983.
Inspire Record 191416 DOI 10.17182/hepdata.30634

The inclusive production of η mesons at CM energies around 34 GeV has been studied for e + e − annihilation into hadrons. The average number of η-mesons per event is found to be 0.72 ± 0.10 (stat.) ± 0.18 (syst.). The abundance of η's is studied as a function of event shape parameters and it is compared to the corresponding π 0 rates.

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DATA REQUESTED FROM AUTHORS.


A Measurement of the Reaction $e^+ e^- \to e^+ e^- \eta^\prime$ and the Radiative Width $\Gamma (\eta^\prime \to \gamma \gamma$) at {PETRA}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 113 (1982) 190-194, 1982.
Inspire Record 177090 DOI 10.17182/hepdata.30958

The reaction e + e - → e + e - η' has been observed in the JADE experiment at PETRA, by detecting the final state π + π - γ, resulting from the decay η' → γϱ 0 . The cross section was measured at an average beam energy of 17.15 GeV to be σ(e + e - → e + e - η') = 2.2 ± 0.2 (stat.) ± 0.4(syst.) nb, yielding the radiative width Γ η'γγ = 5.0 ± 0.5(stat.) ± 0.9 (syst.) keV.

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Charged $D^*$ Production in $e^+ e^-$ Annihilation

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 146 (1984) 121-125, 1984.
Inspire Record 202785 DOI 10.17182/hepdata.30496

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Inclusive Production of Vector Mesons $\rho^0$ and $K^{*\pm}$ in $e^+ e^-$ Annihilation at $\left<\sqrt{s}\right> = 35$-{GeV}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 145 (1984) 441-447, 1984.
Inspire Record 203145 DOI 10.17182/hepdata.30510

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RHO0 CROSS SECTION HAS BEEN EXTRAPOLATED OUTSIDE TO 0.1 < X < 0.7 RANGE.

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