Edwards, C.
E+ E- Scattering
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Measurement of the Reaction $e^+ e^- \to \gamma \gamma$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 94 (1980) 87-90, 1980.
Inspire Record 153120 DOI 10.17182/hepdata.27174

The differential cross section for the reaction e + e − → γγ has been measured in the CMS energy range between 9.4 and 31.6 GeV. The results are found to be in agreement with the predictions of quantum electrodynamics up to momentum transfers- q 2 of 900 GeV 2 . The data set lower limits of about 40 GeV on QED cut-off parameters. We have searched for the decay υ (9.46) → γγ and obtain an upper limit Γ ( υ → γγ )/ Γ ( υ → all) < 1.4% (95% c.l.).

1 data table
Table 1

No description provided.


Observation of a Fourth Upsilon State in e+ e- Annihilations

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Cabenda, R. ; et al.
Phys.Rev.Lett. 45 (1980) 219, 1980.
Inspire Record 153182 DOI 10.17182/hepdata.20674

A fourth state in the upsilon energy region has been seen in e+e− collisions at the Cornell Electron Storage Ring. A resonance is observed with a mass 1112±5 MeV above the lowest upsilon state. The 9.6-MeV rms width is greater than the 4.6-MeV energy resolution of the e+e− beams. The observed characteristics of the new state make it a likely candidate for the 4S3 state of the bb¯ system, lying above the threshold for the production of B mesons.

1 data table
Table 1

NOT CORRECTED FOR TAU HEAVY LEPTON PRODUCTION NOR TWO-PHOTON COLLISIONS.


Test of {QED} in $e^+ e^-$ Annihilation at Energies Between 12-{GeV} and 31.6-{GeV}

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 94 (1980) 259-265, 1980.
Inspire Record 153127 DOI 10.17182/hepdata.45228

We have measured the reactions e + e − → e + e − → μ + μ − and e + e − → γγ at c.m. energies between 12 and 31.6 GeV. Excellent agreement with the predictions of QED has been found, resulting in cut off parameters Λ + > 112 GeV and Λ − > 139 GeV for the first process and Λ + > 34 GeV and Λ − > 42 GeV (95% c.1.) for the last one. A limit on the Weinberg angle of sin 2 θ W < 0.55 (95% c.1.) has been obtained.

3 data tables
Table 1

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 2

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 3

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.


rivet Analysis
Total Cross-section for Hadron Production by Electron - Positron Annihilation at Adone

Ambrosio, M. ; Paternoster, G. ; Tortora, L. ; et al.
Phys.Lett.B 91 (1980) 155-160, 1980.
Inspire Record 152630 DOI 10.17182/hepdata.27239

The total cross section for electron-positron annihilation into three or more hadrons has been measured for centre of mass energies between 1.4 and 2.0 GeV. The data were obtained at ADONE by the BB̄ experiment.

1 data table
Table 1

NOTE THAT THIS MEASUREMENT OF R EXCLUDES TWO-BODY FINAL STATE EVENTS. RADIATIVE CORRECTIONS WERE APPLIED.


Observation of Three Upsilon States

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Billing, M. ; et al.
Phys.Rev.Lett. 44 (1980) 1108, 1980.
Inspire Record 152393 DOI 10.17182/hepdata.20733

Three narrow resonances have been observed in e+e− annihilation into hadrons at total energies between 9.4 and 10.4 GeV. Measurements of mass spacing and ratios of lepton pair widths support the interpretation of these "ϒ" states as the lowest triplet-S levels of the bb¯ quark-antiquark system.

1 data table
Table 1

No description provided.


Test of {QED} in the Reactions $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \mu^+ \mu^-$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Z.Phys.C 4 (1980) 269, 1980.
Inspire Record 152289 DOI 10.17182/hepdata.15600

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


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).


Search for Narrow Resonances in $e^+ e^-$ Annihilation at c.m. Energies Between 29.90-{GeV} and 31.46-{GeV}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 91 (1980) 152-154, 1980.
Inspire Record 152290 DOI 10.17182/hepdata.27258

A search for narrow resonances in e + e − annihilation at c.m. energies between 29.90 and 31.46 GeV provides no evidence for the existence of such states. The 90% confidence upper limit on the integrated resonance cross section is 38 nb MeV, significantly below the value expected for the lowest (t,t̄) bound state.

1 data table
Table 1

No description provided.


Two Particle Correlations in $e^+ e^-$ Annihilation

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 90 (1980) 312, 1980.
Inspire Record 144112 DOI 10.17182/hepdata.27256

We present measurements of two-particle angular correlations in hadron jets produced in e + e − annihilation between 7.7 and 31.6 GeV c.m. energy. The data are compared to predictions of high order perturbative QCD calculations.

1 data table
Table 1

No description provided.


Observation of Planar Three Jet Events in e+ e- Annihilation and Evidence for Gluon Bremsstrahlung

The JADE collaboration Bartel, W. ; Canzler, T. ; Cords, D. ; et al.
Phys.Lett.B 91 (1980) 142-147, 1980.
Inspire Record 143985 DOI 10.17182/hepdata.6339

Topological distributions of charged and neutral hadrons from the reaction e + e − → multihadrons are studied at √ s of about 30 GeV. An excess of planar events is observed at a rate which cannot be explained by statistical fluctuations in the standard two-jet process. The planar events, mostly consisting of a slim jet on one side and a broader jet on the other, are shown actually to possess three-jet structure by demonstrating that the broader jet itself consists of two collinear jets in its own rest system. Detailed agreement between data and predictions is obtained if the process e + e − →q q ̄ g is taken into account. This strongly suggests gluon bremsstrahlung as the origin of the planar three-jet events. By comparison of the data with the qq̄g-model we obtain a value for the strong coupling constant of α S ( q 2 = 0.17 ± 0.04.

2 data tables
Table 1

THRUST AND PLANARITY DISTRIBUTIONS. FINAL (BETTER) THRUST DISTRIBUTIONS WITH DETECTOR CORRECTIONS TO BE PUBLISHED LATER.

Table 2

No description provided.