Loopfest XXII

Session

Session 3

21 May 2024, 09:00

Fondren Science Building 123 (Dallas Texas USA)

Conveners

Session 3

• Ciaran Williams (SUNY Buffalo)
• Radja Boughezal

12. Approximate N3LO PDFs with theoretical uncertainties - MSHT20aN3LO Review

Thomas Cridge (DESY)

21/05/2024, 09:00

We will review the extension of the MSHT20 PDFs to approximate N3LO order and the consequences for phenomenology. We first describe the inclusion of the known N3LO information and the parameterisation of the remaining missing N3LO contributions, as well as the determination of the theoretical uncertainties from missing pieces and higher orders and their interpretation. We then examine the...

15. Progress in the CTEQ-TEA global QCD analysis

Marco Guzzi (Kennesaw State University)

21/05/2024, 09:35

I report on the progress in the precision studies of hadronic parton distributions by the CTEQ-TEA (Tung Et Al.) group.

26. Perturbative calculations for first-principle parton distribution functions

Tobias Neumann (William & Mary)

21/05/2024, 10:10

Parton distribution functions (PDFs) are of key interest in both particle and nuclear physics. At the LHC, the limited knowledge of PDFs is currently one of the leading bottlenecks in precise predictions. In nuclear physics, PDFs provide insight into the structure of the nucleon, towards more complicated systems.

In this talk I will first motivate the need for precise PDFs, then explain how...

28. The NNLO soft function for N-jettiness in hadronic collisions

Rudi Rahn (University of Vienna)

21/05/2024, 11:15

In this talk I'll present our recent work calculating the N-jettiness soft function, based on an extension of the SoftSERVE framework to the general case of N+2 jets and beams for a priori general global observables. I will comment on our approach, present an explicit grid scanning the 2-jettiness soft function, and shed some light on the behaviour of the N-jettiness soft function at the...

18. Improving alpha_s extractions from collider data

Xiaoyuan Zhang

21/05/2024, 11:50

Measuring the strong coupling constant from high-energy collider data with precision comparable to the lattice has been a persistent challenge. For e+e- event shapes, a long-standing discrepancy between extractions from thrust and heavy jet mass may be due to physics in the trijet region. In particular, there is Sudakov shoulder in heavy-jet mass but not thrust which we now know how to resum...

20. Definitions of fragmentation functions and the implications for sum rules

Ted Rogers (Old Dominion University)

21/05/2024, 12:25

I will discuss issues that arise from the mismatch between asymptotic states and partonic states in the formal definitions of fragmentation functions. I will show that standard derivations of common sum rules need to be modified for gauge theories, and discuss several possibilities for constructing more precise definitions. Implications for phenomenological applications will also be discussed.