We review progress in the global QCD analysis by the CTEQ-TEA group since the publication of CT18 parton distribution functions (PDFs) in the proton. Specifically, we discuss comparisons of CT18 NNLO predictions with the LHC 13 TeV measurements as well as with the FNAL SeaQuest and BNL STAR data on lepton pair production. The specialized CT18X PDFs approximating saturation effects are compared with the CT18sx PDFs obtained using NLL/NLO small-$$x$$ resummation. Short summaries are presented for the special CT18 parton distributions with fitted charm and with lattice QCD inputs. A recent comparative analysis of the impact of deuteron nuclear effects on the parton distributions by the CTEQ-JLab and CTEQ-TEA groups is summarized. 
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                            WG1: Summary Structure Functions and Parton Densities
                        
                    
    
            Presentations on ''Structure Functions and Parton Densities'' working group are summarized. They include results from various global analyses for the parton distribution functions (PDFs) inside the proton and nucleus, and the impact of new experimental data and progress in theoretical calculations, on the extraction of PDFs. Various studies were also presented regarding the constraints on the proton and nuclear PDFs from some specific experimental data from the LHC, HERA and RHIC, and elsewhere. 
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                            - Award ID(s):
- 1719914
- PAR ID:
- 10201135
- Date Published:
- Journal Name:
- Proceedings of Science
- Volume:
- 352
- Page Range / eLocation ID:
- 279
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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