A matrix-element-based modification of the parton shower

The transverse momentum distribution of W+/- bosons at hadron colliders is well described by a parton-shower model for small pT values, but not for large ones. This article is an attempt to give a better description of the distribution by using corrections derived from the matrix-element formalism. The parton shower for qqbar->W+/- has been modified to resemble the matrix elements of qqbar->gW and qg->q’W at large pT values. Comparisons between different approaches are presented at sqrt{s}=1800 GeV. The results are also compared with experimental data from the D0 collaboration at Fermilab.