We present various recent updates related to the MSHT20 PDF sets, and particularly to the MSHT20 approximate N3LO (aN3LO) PDFs. These include an investigation of including either inclusive jet data or dijet data, the detailed treatment of ZpT data, and the impact on the gluon PDF in particular. We also very briefly summarize the determination of the strong coupling via an aN3LO global PDF fit, finding αS(MZ2)=0.1170±0.0016, and of including QED corrections in the aN3LO analysis. Finally we consider the preliminary finding associated with the effect of improved knowledge of the N3LO splitting functions on the aN3LO PDFs. In particular we note a moderate impact on the gluon distribution, i.e. within the uncertainty, and a more limited impact on the gluon-gluon luminosity unless strong rapidity cuts are imposed. Hence, we conclude that while details of our aN3LO PDFs will change with more precise splitting functions, only relatively minor effects on predictions are likely to result.
Cite
@article{arxiv.2408.10008,
title = {MSHT Updates 2024},
author = {R. S. Thorne and T. Cridge and L. Harland-Lang},
journal= {arXiv preprint arXiv:2408.10008},
year = {2024}
}