Scaled momentum spectra in deep inelastic scattering at HERA
arXiv:1001.4026 · doi:10.1007/JHEP06(2010)009 10.1007/JHEP10(2010)030
Abstract
Charged particle production has been studied in neutral current deep inelastic ep scattering with the ZEUS detector at HERA using an integrated luminosity of 0.44 fb^-1. Distributions of scaled momenta in the Breit frame are presented for particles in the current fragmentation region. The evolution of these spectra with the photon virtuality, Q^2, is described in the kinematic region 10<Q^2<41000 GeV^2. Next-to-leading-order and modified leading-log-approximation QCD calculations as well as predictions from Monte Carlo models are compared to the data. The results are also compared to e+e- annihilation data. The dependences of the pseudorapidity distribution of the particles on Q^2 and on the energy in the γp system, W, are presented and interpreted in the context of the hypothesis of limiting fragmentation.
44 pages, 11 figures, 21 tables