Berger, Christoph
E+ E- --> HADRONS
Integrated Cross Section
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rivet Analysis
Cross-Sections and Event Topologies in e+ e- Annihilation at 13-GeV and 17-GeV Observed with the PLUTO Detector

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 81 (1979) 410-415, 1979.
Inspire Record 140294 DOI 10.17182/hepdata.45239

First results from the magnetic detector PLUTO at the new e + e − storage ring PETRA are shown. The ratio R of the cross section for hadron production to that for μ-pair production has been measured to be R = 5.0 ± 0.5 at 13 GeV and 4.3 ±0.5 at 17 GeV. Both values have an additional systematic error of 20%. The events show a typical 2-jet structure. The mean transverse momentum approaches a constant value with increasing energy implying a shrinkage of the jet opening angle.

2 data tables
Table 1

TAU HEAVY LEPTON PAIR CONTRIBUTIONS HAVE BEEN SUBTRACTED. R AT 13 AND 17 GEV, TOGETHER WITH SOME SELECTED LOWER ENERGY MEASUREMENTS FROM PLUTO AT DORIS.

Table 2

Data from earlier preprint DESY-79-06. NUMERICAL VALUES MEASURED OFF GRAPH IN PREPRINT.


rivet Analysis
Measurement of the total cross section for e+ e- --> hadrons at s**(1/2) = 10.52-GeV.

The CLEO collaboration Ammar, R. ; Baringer, Philip S. ; Bean, A. ; et al.
Phys.Rev.D 57 (1998) 1350-1358, 1998.
Inspire Record 445351 DOI 10.17182/hepdata.47132

Using the CLEO detector at the Cornell Electron Storage Ring, we have made a measurement of R=sigma(e+e- ->hadrons)/sigma(e+e- ->mu+mu-) =3.56+/-0.01+/-0.07 at ECM=10.52 GeV. This implies a value for the strong coupling constant of alpha_s(10.52 GeV)=0.20+/-0.01+/-0.06, or alpha_s(M_Z)=0.13+/-0.005+/-0.03.

2 data tables
Table 1

Corrected for background and radiactive effects.

Table 2

Value of ALPHAS, the strong coupling constant, from the measurement of R. CT,= ALPHAS also given evolved to the Z0 mass.


First Measurements of Hadronic Decays of the $Z$ Boson

The MARK-II collaboration Abrams, G.S. ; Adolphsen, Chris ; Aleksan, R. ; et al.
Phys.Rev.Lett. 63 (1989) 1558, 1989.
Inspire Record 282670 DOI 10.17182/hepdata.20044

We have observed hadronic final states produced in the decays of Z bosons. In order to study the parton structure of these events, we compare the distributions in sphericity, thurst, aplanarity, and number of jets to the predictions of several QCD-based models and to data from lower energies. The data and models agree within the present statistical precision.

5 data tables
Table 1

Corrected event shape distributions.

Table 2

Corrected event shape distributions.

Table 3

Corrected event shape distributions.

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rivet Analysis
Measurement of the Total Hadronic Cross-section in $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

The MARK-II collaboration Von Zanthier, Christoph ; de Boer, W. ; Grindhammer, Guenter ; et al.
Phys.Rev.D 43 (1991) 34-45, 1991.
Inspire Record 295286 DOI 10.17182/hepdata.22852

A precise measurement of the ratio R of the total cross section e+e−→hadrons to the pointlike cross section e+e−→μ+μ− at a center-of-mass energy of 29.0 GeV is presented. The data were taken with the upgraded Mark II detector at the SLAC storage ring PEP. The result is R=3.92±0.05±0.09. The luminosity has been determined with three independent luminosity monitors measuring Bhabha scattering at different angular intervals. Recent calculations of higher-order QED radiative corrections are used to estimate the systematic error due to missing higher-order radiative corrections in the Monte Carlo event generators.

1 data table
Table 1

No description provided.


Measurements of Z Boson Resonance Parameters in e+ e- Annihilation

Abrams, G.S. ; Adolphsen, Chris ; Averill, D. ; et al.
Phys.Rev.Lett. 63 (1989) 2173, 1989.
Inspire Record 281818 DOI 10.17182/hepdata.20033

We have measured the mass of the Z boson to be 91.14±0.12 GeV/c2, and its width to be 2.42−0.35+0.45 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.46±0.10 GeV, corresponding to 2.8±0.6 neutrino species, with a 95%-confidence-level upper limit of 3.9.

1 data table
Table 1

No description provided.


Initial Measurements of Z Boson Resonance Parameters in e+ e- Annihilation

Abrams, G.S. ; Adolphsen, Chris ; Aleksan, R. ; et al.
Phys.Rev.Lett. 63 (1989) 724, 1989.
Inspire Record 280007 DOI 10.17182/hepdata.20034

We have measured the mass of the Z boson to be 91.11±0.23 GeV/c2, and its width to be 1.61−0.43+0.60 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.62±0.23 GeV, corresponding to 3.8±1.4 neutrino species.

1 data table
Table 1

Data now superceded.


rivet Analysis
Energy-energy Correlations in $e^+ e^-$ Annihilation Into Hadrons

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 99 (1981) 292, 1981.
Inspire Record 156315 DOI 10.17182/hepdata.6228

Measurements of energy-energy correlations in hadronic final states produced in e + e − annihilation at c.m. energies between 7.7 and 31.6 GeV are presented. The data are compared to perturbative QCD predictions. Good qualitative agreement above 20 GeV c.m. energy is found. The importance of non-perturbative effects is discussed, as well as the detailed behaviour of the correlation near 180°.

6 data tables
Table 1

No description provided.

Table 2

OPPOSITE SIDE ENERGY-ENERGY CORRELATIONS NEAR 180 DEG.

Table 3

ENERGY-ENERGY CORRELATION INTEGRATED IN THE REGION 60 TO 120 DEG.

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rivet Analysis
Search for Narrow Resonances in $e^+ e^-$ Annihilation at {PETRA}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 91 (1980) 148-151, 1980.
Inspire Record 152291 DOI 10.17182/hepdata.27236

We have performed a search for narrow resonances in the center of mass energy range from 29.90 to 31.46 GeV using the e + e − storage ring PETRA at DESY. We present the total cross section for hadron production and an upper limit for resonance production, indicating that no bound state of charge- 2 3 quarks exists in this energy range.

2 data tables
Table 1

AVERAGE VALUE OF R OVER THE SCAN REGION.

Table 2

THESE MEASUREMENTS COMBINED WITH PREVIOUS DATA AT 30.0 AND 31.6 GEV REPORTED IN CH. BERGER ET AL., PL 86B, 413 (1979).


rivet Analysis
Search for a 'Top' Threshold in Hadronic $e^+ e^-$ Annihilation at Energies Between 22-{GeV} and 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 86 (1979) 413-417, 1979.
Inspire Record 142517 DOI 10.17182/hepdata.27295

Results on e + e − annihilation into hadrons at c.m. energies between 22 and 31.6 GeV are presented. The data were accumulated with the PLUTO detector at PETRA. The events are dominantly of the two-jet type. The value of the relative hadronic cross section R =3.88 ± 0.22 along with the details of the sphericity and thrust distribution rule out an open (tt̄) channel (Q t = 2 3 ) below 30 GeV. The inclusive muon results support the above conclusion.

1 data table
Table 1

CROSS SECTIONS CORRECTED FOR BEAM-GAS SCATTERING BACKGROUND, INITIAL STATE RADIATION, TAU HEAVY LEPTON CONTRIBUTION AND TWO-PHOTON EVENTS.


Results from pluto at petra

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
1 (1979) 343-349, 1979.
Inspire Record 148976 DOI 10.17182/hepdata.45229

None

1 data table
Table 1

No description provided.