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arXiv · hep-ph/0201192

The Underlying Event in Hard Scattering Processes

R. D. Field
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Abstract

We study the behavior of the "underlying event" in hard scattering proton-antiproton collisions at 1.8 TeV and compare with the QCD Monte-Carlo models. The "underlying event" is everything except the two outgoing hard scattered "jets" and receives contributions from the "beam-beam remnants" plus initial and final-state radiation. The data indicate that neither ISAJET or HERWIG produce enough charged particles (with PT > 0.5 GeV/c) from the "beam-beam remnant" component and that ISAJET produces too many charged particles from initial-state radiation. PYTHIA which uses multiple parton scattering to enhance the "underlying event" does the best job describing the data.

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R. D. Field. 2002-01-21. The Underlying Event in Hard Scattering Processes. https://arxiv.org/abs/hep-ph/0201192

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