Four-jet production at LEP2
- CERN, CH-1211 Geneve 23 (Switzerland)
A selection of four-jet events from ALEPH data at 133 GeV revealed an excess of data over Standard Model expectation, and a strong clustering in the di-jet mass sum distribution close to 105 GeV/c{sup 2}. Only one event had more that one jet tagged as a b-quark, disfavouring hA production as an explanation. However, kinematic and jet-charge properties of the events did not appear consistent with QCD expectation. Including data collected in 1996 at energies of 161 and 172 GeV, ALEPH observed 18 events in the range 106{+-}5 GeV/c{sup 2}, for an expectation of 3.1 from Standard Model processes. DELPHI, L3 and OPAL have designed selections to reproduce the ALEPH analysis, which have similar efficiencies and mass resolutions. None of the other experiments observes either an overall excess or a clustering of events in di-jet mass sum. The probabilities of statistical fluctuation of background, and of a signal consistent with all four experiments, are approximately equal at {approx}7x10{sup -4}.
- OSTI ID:
- 21179581
- Journal Information:
- AIP Conference Proceedings, Vol. 415, Issue 1; Conference: Workshop on beyond the standard model, Balholm (Norway), 29 Apr - 4 May 1997; Other Information: DOI: 10.1063/1.54459; (c) 1997 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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