The chain MadGraph5_aMC@NLO – aMCfast – APPLgrid will allow one to include, in a straighforward manner, any present or future LHC measurement in an NLO global PDF analysis.
The basic idea behind the use of these three codes is that of computing user-defined observables relevant to arbitrary processes, and to represent them in terms of look-up grids, which can be accessed at later times, and used to obtain predictions for such observables with any PDFs. This a-posteriori computation is both accurate and very fast. Contrary to other APPLgrid application, factorisation scale variation can be performed without linking to any third-party code.
The following representative figures show the rapidity of the top quark in top-pair production and the lepton-pair invariant mass in dilepton production in association with one jet at the 14 TeV LHC. For more details, please refer to the original publication.
Currently, the aMCfast interface gives the possibility to produce interpolation grids in the APPLgrid format only when running MadGraph5_aMC@NLO in the Fixed-Order (FO) mode (LO and NLO) in the Standard Model. However, we are presently working in order to extend the same functionalities to the case of FO plus parton shower.
If you use aMCfast in a scientific work, we kindly ask you to follow this citation policy.