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Monte Carlo models of DIS e-gamma scattering must describe hard emissions as well as the soft and collinear limits. Comparison with the observed experimental hadronic energy flow has shown that various models underestimate the high-p_T contribution, in particular at low-x. We have attempted to tune the Herwig, Pythia and Ariadne models to improve the agreement with the data, and to understand the

In Z0 decay into prompt charmonium, i.e. charmonium not originating from B-meson decays, the most important contribution is expected to come from colour-octet mechanisms. However, previous fixed-order calculations of the colour-octet contribution contain large logarithms which, in a more complete treatment, should be resummed to all orders. We study this resummation by using a Monte Carlo QCD casc

We present an implementation of heavy quarkonium production within a perturbative QCD cascade based on the Color Dipole Cascade model. We consider the processes most relevant in the context of the ψ′ surplus at the Tevatron; g → ψ′ and c → ψ′ in the color-singlet model and g → ψ′ through the color-octet mechanism. Our implementation is, however, easily extendible to other quarkonia and other produ

I argue that the success of recently proposed models describing events with large rapidity gaps in DIS at HERA in terms of non-perturbative colour exchange is heavily reliant on suppression of perturbative gluon emission in the proton direction. There is little or no physical motivation for such suppression and I show that a model without this suppression cannot describe the rapidity gap events at

Reconnections among the produced colour dipoles in the Dipole Cascade Model are discussed, and an implementation in theAriadne program is presented. The reconnections are shown to have only small effects on event shapes at LEP 1, on theW mass determination at LEP 2 and on rapidity gaps in deep inelastic scattering at HERA.

AIM: We assessed whether baseline measurements of physical activity, aerobic fitness, body fat and abdominal fat were predictors of changes in body fat measurements over a two-year period.METHODS: The study comprised of 204 children aged 9.8 ± 0.6 years with a normal body mass distribution, who recruited from four schools in middle-class areas of Malmö, Sweden, from 2001 to 2004. Peak oxygen uptak

A laser-based technique for recording absolute air-fuel ratio maps in a single-laser pulse in combustion devices, for instance, prior to ignition in internal combustion engines, is demonstrated. The method is based on an in situ pulse-to-pulse calibration of two-dimensional laser-induced fluorescence (LIF) images of relative fuel distributions by a point Raman measurement. A single excimer laser p

The jet structure in events with Drell-Yan-produced W bosons is discussed, and a new model for describing such an event is presented. The model is shown to explain recent measurements of the W-jet rapidity correlation and predicts a transverse energy flow at high W rapidities (corresponding to probing small-x partons in one of the incoming protons) higher than conventional parton cascade event gen