Validation test of the NNPDF4.0-MC family of PDF sets. These are PDF similar to NNPDF4.0 with some key differences:
The fit is parametrized at Q = 1 GeV (perturbative charm)
Positivity is enforced at Q = 1 GeV in the evolution basis to avoid any negative points.
The charm threshold is displaced to Q = 3 GeV to avoid the negative contribution of the matching conditions.
Small oscillations in extreme regions of the phase space are smoothed out using a gaussian filter.
The photon is added from NNPDF40_nnlo_as_01180_qed
These PDFs are:
Comparisons to the perturbative charm variant of NNPDF4.0 Note that the evolution differs due to the displacement of the charm threshold and the usage of exact evolution instead of truncated.
The comparisons are shown at the fitting scale of Q = 1 GeV, at scale slightly above the charm and bottom thresholds (Q = 10 GeV) and at a more typical scale of Q = 100 GeV
Comparisons with other LO PDF sets commonly used and with only the latest LO set from NNPDF / CT / MSHT
For the report below only NNPDF sets are considered. The NNPDF4.0 MC LO / NLO / NNLO sets are compared to NNPDF23 LO for different values of Q and in extreme regions of the phasespace (x -> 1e-10 and zoom in to x -> 1.)