Date

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

No description provided.


STUDY OF (PI+ PI- PI+ PI-) AND (PI+ PI- PI0) CHANNEL IN E+ E- ANNIHILATION AT 1.450-GEV - 1.875-GEV center-of-mass ENERGY

Esposito, B. ; Marini, A. ; Ronga, F. ; et al.
Lett.Nuovo Cim. 28 (1980) 195-200, 1980.
Inspire Record 158282 DOI 10.17182/hepdata.37366

None

2 data tables

No description provided.

POSSIBLE EVIDENCE FOR OMEGA(1670) RESONANCE.


MEASUREMENTS OF THE EM TIMELIKE FORM-FACTORS FOR KAON AND PION AT S**(1/2) = 1.5-GEV

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.
Lett.Nuovo Cim. 28 (1980) 337-342, 1980.
Inspire Record 158283 DOI 10.17182/hepdata.37369

None

1 data table

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

No description provided.

No description provided.


EXPERIMENTAL STUDY OF HEAVY CHARGED LEPTONS AT PETRA

Barber, D.P. ; Becker, U. ; Bei, G.D. ; et al.
Phys.Rev.Lett. 45 (1980) 1904-1907, 1980.
Inspire Record 158858 DOI 10.17182/hepdata.20675

Data from the MARK-J detector on the reactions e+e−→μ+μ−, τ+τ− in the center-of-mass energy range from 12 to 36.7 GeV are presented. The μ, τ radii are shown to be <10−16 cm. A search has been made for the production of a new heavy lepton and for the production of spin-0 supersymmetric partners of the muon. 95%-confidence-level lower limits of 16 GeV for the mass of a new charged heavy lepton and 15 GeV for the mass of the scalar partners of the muon are obtained.

1 data table

No description provided.


Observation of Upsilon, Upsilon', and Upsilon'' at the Cornell electron Storage Ring

Bohringer, T. ; Costantini, F. ; Dobbins, J. ; et al.
Phys.Rev.Lett. 44 (1980) 1111-1114, 1980.
Inspire Record 157729 DOI 10.17182/hepdata.20731

The ϒ, ϒ′, and ϒ′′ states have been observed at the Cornell Electron Storage Ring as narrow peaks in σ(e+e−→hadrons) versus beam energy. Data were collected during a run with integrated luminosity of 1000 nb−1, using the Columbia University-Stony Brook segmented NaI detector. The measured mass differences are M(ϒ′)−M(ϒ)=559±1(±3) MeV and M(ϒ′′)−M(ϒ)=889±1(±5) MeV, where the errors in parentheses represent systematic uncertainties. Preliminary values for the leptonic width ratios were also obtained.

1 data table

HADRONIC EVENTS/SMALL-ANGLE BHABHA YIELD.


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

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

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

No description provided.


Rapid Growth of Charged Particle Multiplicity in High-Energy e+ e- Annihilations

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 89 (1980) 418-422, 1980.
Inspire Record 143691 DOI 10.17182/hepdata.27273

Hadron production by e + e − annihilation has been studied for c.m. energies W between 13 and 31.6 GeV. As a function of 1n W the charged particle multiplicity grows faster at high energy than at lower energies. This is correlated with a rise in the plateau of the rapidity distribution. The cross section s d σ /d x is found to scale within ±30% for x > 0.2 and 5 ⩽ W ⩽ 31.6 GeV.

7 data tables

CHARGED PARTICLE MULTIPLICITIES.

RAPIDITY DISTRIBUTION.

RAPIDITY DISTRIBUTION.

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E+ e- Annihilation at High-Energies and Search for the t-Quark Continuum Contribution

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Z.Phys.C 4 (1980) 87, 1980.
Inspire Record 143690 DOI 10.17182/hepdata.15599

Measurements ofR, sphericity and thrust are presented for c.m. energies between 12 and 31.6 GeV. A possible contribution of at\(\bar t\) continuum can be ruled out for c.m. energies between 16 and 31 GeV.

1 data table

No description provided.