NLO matrix elements and truncated showers

In this publication, an algorithm is presented that combines the ME+PS approach to merge sequences of tree-level matrix elements into inclusive event samples [1] with the Powheg method, which combines exact next-to-leading order matrix element results with the parton shower [2, 3]. It was developed in parallel to the MEnloPS technique discussed in [4] and has been implemented in the event generator Sherpa [5, 6]. The benefits of this approach are exemplified by some first predictions for a number of processes, namely the production of jets in e + e −-annihilation, in deep-inelastic ep scattering, in association with single W, Z or Higgs bosons, and with vector boson pairs at hadron colliders.