The 1 → 3 massive splitting functions from QCD factorization and SCET

• Published in: The journal of high energy physics Vol. 2024; no. 7; pp. 80 - 23
• Main Authors: Craft, Evan, Gonzalez, Mark, Lee, Kyle, Meçaj, Bianka, Moult, Ian
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 09.07.2024; Springer Nature B.V; SpringerOpen
• Subjects: Agreements; Classical and Quantum Gravitation; Effective Field Theories of QCD; Elementary Particles; Factorization; Flavor (particle physics); Gauge theory; Higher-Order Perturbative Calculations; Ingredients; Jets and Jet Substructure; Kinematics; Partons; Physics; Physics and Astronomy; Quantum chromodynamics; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Quarks; Regular Article - Theoretical Physics; Relativity Theory; Renormalization Group; Splitting; String Theory; Effective Field Theories of QCD; Renormalization Group; Jets and Jet Substructure; Factorization; Higher-Order Perturbative Calculations
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP07(2024)080

A bstract Splitting functions are universal functions describing the collinear dynamics of gauge theories, and as such are crucial ingredients for a wide variety of calculations in perturbative QCD. We present analytic results for the triple collinear splitting functions in QCD with a single massive parton. We derive the splitting functions using two distinct methods; first by expanding the squared matrix elements in the collinear limit, and secondly by using soft-collinear effective theory with massive quarks. We find agreement between these two approaches, providing a strong check of our results. Additionally, we also check all iterated and soft limits of our results, finding agreement with predictions from factorization. Our results provide an important ingredient for higher order perturbative calculations involving massive partons, and for the description of the collinear dynamics of heavy flavor jets.