Renormalization and scale evolution of the soft-quark soft function

Journal Article · Thu Jul 16 00:00:00 UTC 2020 · Journal of High Energy Physics (Online)

DOI: https://doi.org/10.1007/JHEP07(2020)104 · OSTI ID:1646660

Liu, Ze Long ^[1]; Mecaj, Bianka ^[2]; Neubert, Matthias ^[3]; Wang, Xing ^[2]; Fleming, Sean ^[2]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); OSTI
2. Johannes Gutenberg Univ., Mainz (Germany). PRISMA+ Cluster of Excellence. Mainz Inst. for Theoretical Physics
3. Johannes Gutenberg Univ., Mainz (Germany). PRISMA+ Cluster of Excellence. Mainz Inst. for Theoretical Physics; Cornell Univ., Ithaca, NY (United States). Dept. of Physics

Soft functions defined in terms of matrix elements of soft fields dressed by Wilson lines are central components of factorization theorems for cross sections and decay rates in collider and heavy-quark physics. While in many cases the relevant soft functions are defined in terms of gluon operators, at subleading order in power counting soft functions containing quark fields appear. We present a detailed discussion of the properties of the soft-quark soft function consisting of a quark propagator dressed by two finite-length Wilson lines connecting at one point. This function enters in the factorization theorem for the Higgs-boson decay amplitude of the h → γγ process mediated by light-quark loops. We perform the renormalization of this soft function at one-loop order, present a conjecture for its two-loop anomalous dimension and discuss solutions to its renormalization-group evolution equation in momentum space, in Laplace space and in the “diagonal space”, where the evolution is strictly local in the momentum variable.

• Research Organization: Johannes Gutenberg Univ., Mainz (Germany); Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Univ. of Arizona, Tucson, AZ (United States)
• Sponsoring Organization: German Research Foundation (DFG); USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: 89233218CNA000001; AC52-06NA25396; FG02-04ER41338
• OSTI ID: 1646660
• Report Number(s): LA-UR--20-28935
• Journal Information: Journal of High Energy Physics (Online), Journal Name: Journal of High Energy Physics (Online) Journal Issue: 7 Vol. 2020; ISSN 1029-8479
• Publisher: Springer BerlinCopyright Statement
• Country of Publication: United States
• Language: English