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1. LHC and DIS experimental datain the CT18(Z) global QCD analysis

   https://doi.org/10.22323/1.352.0021  

   Nadolsky, Pavel ; Hou, Tie-Jiun ; Xie, Keping ; Gao, Jun ; Dulat, Sayipjamal ; Guzzi, Marco ; Huston, Joey Walter ; Hobbs, Timothy J. ; Pumplin, Jon ; Schmidt, Carl ; et al ( August 2019 , Proceedings of science)

   We discuss implementation of the LHC experimental data sets in the new CT18 global analysis of quantum chromodynamics (QCD) at the next-to-next-leading order of the QCD coupling strength. New methodological developments in the fitting methodology are discussed. Behavior of the CT18 NNLO PDFs for the conventional and "saturation-inspired" factorization scales in deep-inelastic scattering is reviewed. Four new families of (N)NLO CTEQ-TEA PDFs are presented: CT18, A, X, and Z. 

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2. New CTEQ global analysis with high precision data from the LHC

   https://doi.org/10.22323/1.352.0001  

   Yuan, C. P. ; Hou, Tie-Jiun ; Xie, Keping ; Jun, Gao ; Dulat, Sayipjamal ; Guzzi, Marco ; Hobbs, Timothy J. ; Huston, Joey Walter ; Nadolsky, Pavel ; Pumplin, Jon ; et al ( July 2019 , Proceedings of science)

   We present the new CTEQ-TEA global analysis of quantum chromodynamics (QCD). In this analysis, parton distribution functions (PDFs) of the nucleon are determined within the Hessian method at the next-to-next-to leading order (NNLO) in perturbative QCD, based on the most recent measurements from the Large Hadron Collider (LHC) and a variety of world collider data. Because of difficulties in fitting both the ATLAS 7 and 8 TeV W and Z vector boson production cross section data, we present two families of PDFs, named CT18 and CT18Z PDFs, respectively, without and with the ATLAS 7 TeV W and Z measurements. We study the impact of the CT18 family of PDFs on the theoretical predictions of standard candle cross sections at the LHC. 

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3. NNLO constraints on proton PDFs from the SeaQuest and STAR experiments and other developments in the CTEQ-TEA global analysis

   https://doi.org/10.21468/SciPostPhysProc.8.005  

   Guzzi, Marco ; Hobbs, Timothy ; Hou, Tie-Jiun ; Jing, Xiaoxian ; Xie, Keping ; Courtoy, Aurore ; Dulat, Sayipjamal ; Gao, Jun ; Huston, Joey ; Nadolsky, Pavel ; et al ( January 2022 , SciPost Physics Proceedings)

   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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4. Heavy-flavor impact on CTEQ-TEA global QCD analyses

   https://doi.org/10.1051/epjconf/202227000004  

   Guzzi, Marco ; Ablat, Alim ; Dulat, Sayipjamal ; Hou, Tie-Jiun ; Nadolsky, Pavel ; Sitiwaldi, Ibrahim ; Xie, Keping ; Yuan, C.-P. ( January 2022 , EPJ Web of Conferences)

   Bruno, G.E. ; Chiodini, G. ; Colangelo, P. ; Corianò, C. ; Creanza, D.M. ; De Fazio, F. ; Nappi, E. (Ed.)

   We discuss heavy-flavor production at hadron colliders in recent global QCD analyses to determine parton distribution functions (PDFs) in the proton. We discuss heavy-flavor treatments in precision theory predictions at the LHC. In particular, we discuss factorization schemes in presence of heavy flavors in proton-proton collisions, as well as the impact of heavy-flavor production at the LHC on PDFs. We show results of recent updates beyond CT18, the latest global QCD analysis from the CTEQ-TEA group. 

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5. CTEQ-TEA group updates: Photon PDF and Impact from heavy flavors in the CT18 global analysis

   https://doi.org/10.22323/1.398.0370  

   Guzzi, Marco ; Xie, Keping ; Hou, Tie-Jiun ; Nadolsky, Pavel ; Schmidt, Carl ; Yan, Mengshi ; Yuan, C.-P. ( March 2022 , CTEQ-TEA group updates: Photon PDF and Impact from heavy flavors in the CT18 global analysis)

   Sissa (Ed.)

   We discuss recent CTEQ-TEA group activities after the publication of the CT18 global analysis of parton distribution functions (PDFs) in the proton. In particular, we discuss a new calculation for the photon content in the proton, termed as CT18lux and CT18qed PDFs, and the impact of novel charm- and bottom-quark production cross section measurements at HERA on the CT18 global analysis. 

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