SMEFTsim contains a set of UFO models that have been validated following the recommendations in CERN-LPCC-2019-02 and using the dedicated MadGraph5_aMC@NLO plugin.
The procedure consists in pairwise comparisons between models, based on the values returned for a set of squared amplitudes.
Given a list of 2-->n processes and a list of points in parameter space, the plugin computes the SM squared amplitude, the pure SM-L6 interference and the quadratic L6 contribution at one random phase-space point for each process and parameter point. The validation is considered successful if all the squared amplitudes agree within a permille.
The validation of the SMEFTsim UFOs was performed
- internally, comparing models with same flavor assumptions and different input scheme and viceversa.
- externally, comparing the
general,topandtopU3lmodels with m_W input scheme todim6topandSMEFT@NLO
This repository contains two types of files that have been produced in the validation process:
Each directory cards_MODEL1_to_MODEL2 contains files named param_XX.dat, where XX is the name of a parameter in MODEL2.
This is a parameter card of MODEL1 that corresponds to setting XX = 1 and all other MODEL2 parameters to 0.
These cards were used as input to the validation, and are provided here to aid the translation between different UFO models.
The models are labeled as follows:
general:SMEFTsim_general_MwScheme_UFO_v3_0utf:SMEFTsim_U35_MwScheme_UFO_v3_0MFV:SMEFTsim_MFV_MwScheme_UFO_v3_0top:SMEFTsim_top_MwScheme_UFO_v3_0topU3l:SMEFTsim_topU3l_MwScheme_UFO_v3_0
Labels with an extra A indicate that the alphaScheme is used instead, for instance generalA refers to SMEFTsim_general_alphaScheme_UFO_v3_0.
The label SMEFTatNLO corresponds to the SMEFTatNLO_U2_2_U3_3_cG_4F_LO_UFO model released in 2018, while SMEFTatNLOv1 denotes SMEFTatNLO_v1_0 released in 2020.
The output_PDFs directory contains the PDF files produced as output by the validation plugin.
One file is produced for each comparison.
Discrepancies larger than a permille are marked in red, unless the absolute value of the squared amplitude is smaller than 1e-16 for both models, in which case they are blue.