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arXiv · hep-ex/9810046

Measurement of Three-jet Distributions in Photoproduction at HERA

ZEUS Collaboration
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Abstract

The cross section for the photoproduction of events containing three jets with a three-jet invariant mass of M_3J > 50 GeV has been measured with the ZEUS detector at HERA. The three-jet angular distributions are inconsistent with a uniform population of the available phase space but are well described by parton shower models and O(alpha alpha_s^2) pQCD calculations. Comparisons with the parton shower model indicate a strong contribution from initial state radiation as well as a sensitivity to the effects of colour coherence.

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ZEUS Collaboration. 1998-10-28. Measurement of Three-jet Distributions in Photoproduction at HERA. https://doi.org/10.1016/s0370-2693(98)01360-4

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