Skip to main navigation Skip to search Skip to main content

Measurement of Subjet Multiplicities in Neutral Current Deep Inelastic Scattering at HERA and Determination of αs

  • S. Chekanov
  • , D. Krakauer
  • , J. H. Loizides
  • , S. Magill
  • , B. Musgrave
  • , J. Repond
  • , R. Yoshida
  • , Margarita C. K. Mattingly
  • , P. Antonioli
  • , G. Bari
  • , M. Basile
  • , L. Bellagamba
  • , D. Boscherini
  • , A. Bruni
  • , G. Bruni
  • , G. Cara Romeo
  • , L. Cifarelli
  • , F. Cindolo
  • , A. Contin
  • , M. Corradi
  • S. de Pasquale, P. Giusti, G. Iacobucci, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan, D. Bartsch
  • Argonne National Laboratory
  • Istituto Nazionale di Fisica Nucleare, Sezione di Bologna
  • Universität Bonn

Research output: Contribution to journalArticlepeer-review

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.).
Original languageAmerican English
Pages (from-to)41-58
JournalPhysics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume558
Issue number1-2
DOIs
StatePublished - Apr 10 2003

Disciplines

  • Physics

Cite this