Generic dijet soft functions at two-loop order: correlated emissions

• Published in: The journal of high energy physics Vol. 2019; no. 7; pp. 1 - 57
• Main Authors: Bell, Guido, Rahn, Rudi, Talbert, Jim
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2019; Springer Nature B.V; SpringerOpen
• Subjects: Algorithms; Classical and Quantum Gravitation; Effective Field Theories; Elementary Particles; High energy physics; Parameterization; Perturbative QCD; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; Renormalization Group; Resummation; Singularities; String Theory; Renormalization Group; Effective Field Theories; Resummation; Perturbative QCD
• ISSN: 1029-8479; 1126-6708; 1127-2236; 1029-8479
• DOI: 10.1007/JHEP07(2019)101

A bstract We present a systematic algorithm for the perturbative computation of soft functions that are defined in terms of two light-like Wilson lines. Our method is based on a universal parametrisation of the phase-space integrals, which we use to isolate the singularities in Laplace space. The observable-dependent integrations can then be performed numerically, and they are implemented in the new, publicly available package SoftSERVE that we use to derive all of our numerical results. Our algorithm applies to both SCET-1 and SCET-2 soft functions, and in the current version it can be used to compute two out of three NNLO colour structures associated with the so-called correlated-emission contribution. We confirm existing two-loop results for about a dozen e + e − and hadron-collider soft functions, and we obtain new predictions for the C-parameter as well as thrust-axis and broadening-axis angularities.