Matching NLO with parton shower in Monte Carlo scheme

A new method of including NLO QCD corrections to the hard process in the LO Monte Carlo (MC) shower is discussed. The method is based on a recently proposed MC factorization scheme, which dramatically simplifies the NLO coefficient functions. The NLO corrections are introduced by simple reweighing of the events produced by the LO shower with a single, positive MC weight. A practical implementation of the method is presented for the case of electro-weak boson production in the hadron-hadron collision, and the results are compared with well established approaches to NLO+PS matching.