Published November 17, 1988 | Version v1
Journal article Metadata-only

Analysis of multijet final states in e+e- annihilation

Creators

  • 1. Technische Hochschule Aachen (Germany, F.R.). 1. Physikalisches Inst.
  • 2. Bonn Univ. (Germany, F.R.). Physikalisches Inst.
  • 3. Bristol Univ. (UK). H.H. Wills Physics Lab.
  • 4. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany, F.R.)
  • 5. Dortmund Univ. (Germany, F.R.). Inst. fuer Physik
  • 6. Hamburg Univ. (Germany, F.R.). 2. Inst. fuer Experimentalphysik
  • 7. Imperial Coll. of Science and Technology, London (UK). Dept. of Physics
  • 8. Universidad Autonoma de Madrid (Spain)
  • 9. Oxford Univ. (UK). Dept. of Nuclear Physics
  • 10. Rutherford Appleton Lab., Chilton (UK)
  • 11. Siegen Univ. (Gesamthochschule) (Germany, F.R.). Fachbereich 7 - Physik
  • 12. Weizmann Inst. of Science, Rehovoth (Israel)
  • 13. Wisconsin Univ., Madison (USA). Dept. of Physics

Description

Data accumulated by the TASSO detector across the whole range of energies spanned at PETRA, 12 ≤ √s ≤ 46.8 GeV, have been analysed in terms of cluster algorithms. Using parameters optimised at 35 GeV CM energy, three perturbative QCD+fragmentation models were compared with the data. The O(αs2) model gives too few 4,5-cluster events, implying that higher order QCD contributions are required to describe the data. The parton cascade model, incorporating many orders in perturbation theory, gives a better description of the rates of ≥ 4 clusters, but shows a lack of hard gluon emission by giving too few 3-, and too many 2-cluster events. When hard gluon emission is taken into account, by the cascade model incorporating the O(αs) matrix element, all cluster rates are reproduced well. All the models describe the trend of the evolution of the cluster rates between <√s>=14 and 43.8 GeV. We find that the rate of 3-jet events seen in the data decreases as s increases in a manner consistent with the Q2 dependence of αs as predicted by QCD. (orig.)

Additional details

Publishing Information

Journal Title
Physics Letters, (Section) B
Journal Volume
214
Journal Issue
2
Series
Phys. Lett., B.
Journal Page Range
286-294
ISSN
0370-2693
CODEN
PYLBA

INIS

Country of Publication
Netherlands
Country of Input or Organization
Netherlands
INIS RN
20010299
Subject category
S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
Resource subtype / Literary indicator
Numerical Data
Descriptors DEI
ALGORITHMS; ANNIHILATION; BRANCHING RATIO; CASCADE THEORY; CLUSTER EMISSION MODEL; COMPARATIVE EVALUATIONS; ELECTRON-POSITRON INTERACTIONS; ENERGY DEPENDENCE; GEV RANGE 10-100; GLUONS; HADRONS; JET MODEL; LIMITING FRAGMENTATION; MATRIX ELEMENTS; MULTIPLE PRODUCTION; OPTIMIZATION; PARTON MODEL; PERTURBATION THEORY; QUANTUM CHROMODYNAMICS; THEORETICAL DATA
Descriptors DEC
BOSONS; COMPOSITE MODELS; DATA; ELEMENTARY PARTICLES; ENERGY RANGE; EVALUATION; FIELD THEORIES; GEV RANGE; HYPOTHESIS; INFORMATION; INTERACTIONS; LEPTON-LEPTON INTERACTIONS; MATHEMATICAL MODELS; MULTIPERIPHERAL MODEL; NUMERICAL DATA; PARTICLE INTERACTIONS; PARTICLE MODELS; PARTICLE PRODUCTION; PERIPHERAL MODELS; POSTULATED PARTICLES; QUANTUM FIELD THEORY

Optional Information

Contract/Grant/Project number
Contract DE-AC02-76ER00881; Grant INT-83-13994
Collaborations
TASSO Collaboration.