Matching NLO QCD with parton shower in Monte Carlo scheme – the KrkNLO method

A new method of including the complete NLO QCD corrections to hard processes in the LO parton-shower Monte Carlo (PSMC) is presented. This method, called KrkNLO, requires the use of parton distribution functions in a dedicated Monte Carlo (MC) factorization scheme, which is also discussed in this paper. In the future, it may simplify introduction of the NNLO corrections to hard processes and the NLO corrections to PSMC. Details of the method and numerical examples of its practical implementation as well as comparisons with other calculations, such as MCFM, MC@NLO, POWHEG, for single Z/γ∗-boson production at the LHC are presented. IFJPAN-IV-2015-1 CERN-PH-TH/2015-061 MCnet-15-06 This work is partly supported by the Polish National Science Center grant DEC-2011/03/B/ST2/02632, the Polish National Science Centre grant UMO-2012/04/M/ST2/00240. ar X iv :1 50 3. 06 84 9v 3 [ he pph ] 1 6 N ov 2 01 5