Soft functions for generic jet algorithms and observables at hadron colliders

• Main Authors: Daniele Bertolini, Daniel Kolodrubetz, Duff Neill, Piotr Pietrulewicz, Iain W. Stewart, Frank J. Tackmann, Wouter J. Waalewijn
• Format: Article
• Language: English
• Published: SpringerOpen 2017-07-01
• Series: Journal of High Energy Physics
• Subjects: Jets; NLO Computations
• Online Access: http://link.springer.com/article/10.1007/JHEP07(2017)099

Abstract We introduce a method to compute one-loop soft functions for exclusive N - jet processes at hadron colliders, allowing for different definitions of the algorithm that determines the jet regions and of the measurements in those regions. In particular, we generalize the N -jettiness hemisphere decomposition of ref. [1] in a manner that separates the dependence on the jet boundary from the observables measured inside the jet and beam regions. Results are given for several factorizable jet definitions, including anti-k T , XCone, and other geometric partitionings. We calculate explicitly the soft functions for angularity measurements, including jet mass and jet broadening, in pp → L + 1 jet and explore the differences for various jet vetoes and algorithms. This includes a consistent treatment of rapidity divergences when applicable. We also compute analytic results for these soft functions in an expansion for a small jet radius R. We find that the small-R results, including corrections up to O R 2 $$ \mathcal{O}\left({R}^2\right) $$ , accurately capture the full behavior over a large range of R.