Authors

Document Type

Article

Publication Date

4-10-2003

Abstract

The subjet multiplicity has been measured in neutral current e+p interactions at Q2 > 125 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb-1. Jets were identified in the laboratory frame using the longitudinally invariant kT cluster algorithm. The number of jet-like substructures within jets, known as the subjet multiplicity, is defined as the number of clusters resolved in a jet by reapplying the jet algorithm at a smaller resolution scale ycut. Measurements of the mean subjet multiplicity, (nsbj), for jets with transverse energies ET,jet > 15 GeV are presented. Next-to-leading-order perturbative QCD calculations describe the measurements well. The value of αs(MZ), determined from (nsbj) at ycut = 10-2 for jets with 25 < ET,jet < 71 GeV, is αs(MZ) = 0.1187 ± 0.0017(stat.)-0.0009+0.0024(syst.) -0.0076+0.0093(th.). © 2003 Published by Elsevier Science B.V.

Journal Title

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

Volume

558

Issue

1-2

First Page

41

Last Page

58

DOI

https://doi.org/10.1016/S0370-2693(03)00216-8

First Department

Physics

Acknowledgements

Open access article retrieved April 9, 2021 from https://www.sciencedirect.com/science/article/pii/S0370269303002168

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