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Four-jet final state production in e+e collisions at centre-of-mass energies of 130 and 136 GeV

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Zeitschrift für Physik C Particles and Fields

Abstract

The four-jet final state is analyzed to search for hadronic decays of pair-produced heavy particles. The analysis uses the ALEPH data collected at LEP in November 1995 at centre-of-mass energies of 130 and 136 GeV, corresponding to a total integrated luminosity of 5.7 pb−1. An excess of four-jet events is observed with respect to the standard model predictions. In addition, these events exhibit an enhancement in the sum of the two di-jet masses around 105 GeV/c 2. The properties of these events are studied and compared to the expectations from standard processes and to pair production hypotheses.

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Supported by Dirección General de Investigación Científica y Técnica, Spain

Supported by the Commission of the European Communities, contract ER-BCHBICT941234

Supported by CICYT, Spain

Supported by the National Science Foundation of China

Supported by the Danish Natural Science Research Council

Supported by the UK Particle Physics and Astronomy Research Council

Supported by the US Department of Energy, grant DE-FG0295-ER40896

Supported by the US Department of Energy, contract DE-FG05-92ER40742

Supported by the US Department of Energy, contract DE-FG05-85ER250000

Supported by the Bundesministerium für Forschung und Technologie, Germany

Supported by the Direction des Sciences de la Matière, C.E.A.

Supported by Fonds zur Förderung der wissenschaftlichen Forschung, Austria

Supported by the US Department of Energy, grant DE-FG03-92ER40689

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ALEPH Collaboration., Buskulic, D., De Bonis, I. et al. Four-jet final state production in e+e collisions at centre-of-mass energies of 130 and 136 GeV. Z. Phys. C - Particles and Fields 71, 179–197 (1996). https://doi.org/10.1007/BF02906976

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  • DOI: https://doi.org/10.1007/BF02906976

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