Article

Subjet distributions in deep inelastic scattering at HERA

European Physical Journal C (Impact Factor: 5.25). 63(4):527-548. DOI: 10.1140/epjc/s10052-009-1090-3

ABSTRACT Subjet distributions were measured in neutral current deep inelastic ep scattering with the ZEUS detector at HERA using an integrated luminosity of 81.7pb−1. Jets were identified using the k

T
cluster algorithm in the laboratory frame. Subjets were defined as jet-like substructures identified by a reapplication of
the cluster algorithm at a smaller value of the resolution parameter ycuty_{\rm cut}. Measurements of subjet distributions for jets with exactly two subjets for ycut=0.05y_{\rm cut}=0.05 are presented as functions of observables sensitive to the pattern of parton radiation and to the colour coherence between
the initial and final states. Perturbative QCD predictions give an adequate description of the data.

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