Monte Carlo simulations of Higgs-boson production at the LHC with the KrkNLO method

TL;DR

This paper evaluates the KrkNLO method for matching NLO QCD corrections with parton shower Monte Carlo generators, focusing on Higgs and Drell-Yan processes at the LHC, and compares it with other approaches and experimental data.

Contribution

It provides the first results of the KrkNLO method for Higgs production at the LHC and compares its predictions with other NLO+PS matching methods and experimental data.

Findings

KrkNLO implementation validated in Herwig 7.

Predictions for Higgs production agree with other NLO+PS methods.

Results show good agreement with ATLAS data.

Abstract

We present numerical tests and predictions of the KrkNLO method for matching of NLO QCD corrections to hard processes with LO parton shower Monte Carlo generators (NLO+PS). This method was described in detail in our previous publications, where it was also compared with other NLO+PS matching approaches (MC@NLO and POWHEG) as well as fixed-order NLO and NNLO calculations. Here we concentrate on presenting some numerical results (cross sections and distributions) for $Z/\gamma^*$ (Drell-Yan) and Higgs-boson production processes at the LHC. The Drell--Yan process is used mainly to validate the KrkNLO implementation in the Herwig 7 program with respect to the previous implementation in Sherpa. We also show predictions for this process with the new, complete, MC-scheme parton distribution functions and compare them with our previously published results. Then, we present the first results of the KrkNLO method for Higgs production in gluon-gluon fusion at the LHC and compare them with MC@NLO and POWHEG predictions from Herwig 7 fixed-order results from HNNLO and a resummed calculation from HqT, as well as with experimental data from the ATLAS collaboration.