English

Soft evolution of multi-jet final states

High Energy Physics - Phenomenology 2015-02-19 v2

Abstract

We present a new framework for computing resummed and matched distributions in processes with many hard QCD jets. The intricate color structure of soft gluon emission at large angles renders resummed calculations highly non-trivial in this case. We automate all ingredients necessary for the color evolution of the soft function at next-to-leading-logarithmic accuracy, namely the selection of the color bases and the projections of color operators and Born amplitudes onto those bases. Explicit results for all QCD processes with up to 252\to 5 partons are given. We also devise a new tree-level matching scheme for resummed calculations which exploits a quasi-local subtraction based on the Catani-Seymour dipole formalism. We implement both resummation and matching in the Sherpa event generator. As a proof of concept, we compute the resummed and matched transverse-thrust distribution for hadronic collisions.

Keywords

Cite

@article{arxiv.1411.7325,
  title  = {Soft evolution of multi-jet final states},
  author = {Erik Gerwick and Stefan Hoeche and Simone Marzani and Steffen Schumann},
  journal= {arXiv preprint arXiv:1411.7325},
  year   = {2015}
}

Comments

39 pages, 10 figures. Extended sections 2.0, 2.5 and 3.2. Version accepted by JHEP

R2 v1 2026-06-22T07:13:30.938Z