The total cross section and the inclusive muon cross section for the process e + e − → hadrons have been measured in the center of mass energy range between 39.79 and 46.78 GeV. The ratio R shows no significant structure. It has an average value of 4.13±0.08±0.14. An upper limit is set on the production of narrow resonances. Limits are obtained for pair-produced heavy quarks. The data are compared with the standard electroweak interaction model including QCD corrections taking into account the five known types of quarks. Upper limits are given for a possible structure of quarks and for effects of color octet leptons.
Figure 1 also shows energy scan of 'R'.
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.
TABLES GIVEN HERE CONTAIN SELF CORRELATION. THIS IS SUBTRACTED IN THE FIGURE.
VALUE OF ASSYMETRY IN CORRELATIONS.
No description provided.
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.
ERRORS ARE STATISTICAL PLUS POINT TO POINT SYSTEMATICS. THERE IS AN ADDITIONAL 2.4 PCT OVERALL NORMALIZATION ERROR.
No description provided.
Topological distributions of hadrons from the reaction e + e − → hadrons are studied at center of mass energies of about 33 GeV. The experimental distributions in the parameters acoplanarity and tripodity, both sensitive to events with a four-jet structure, show significant deviations from the expectations for two- and three-jet events. They can be described well by the inclusion of four-jet events. The relative magnitude of the observed effect indicates second order QCD as its probable origin.
No description provided.
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.
No description provided.
WIDTH(Z) = 2.5 GEV WAS ASSUMED. CONST(N=SIN2TW) WAS DETERMINED FROM RATIO(HADRONS/MU). FIRST ORDER QCD.
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.
AVERAGE R VALUE THROUGHOUT ENERGY RANGE. SYSTEMATIC ERROR IS CONSERVATIVE AND WILL BE IMPROVED.
R VALUES AT 20 MEV STEPS. DATA TAKEN FROM TABLE IN THE PREPRINT.