Automated calculation of two-loop soft functions in SCET

  • July 13, 2018, 2:30 pm US/Central
  • Wilson Hall, Curia II
  • Rudi Rahn, Bern University
  • Claudius
  • InSpire profile
Perturbative calculations for many collider observables suffer from
large logarithmic corrections associated with soft emissions or
radiation collinear to beam or jet directions. Resummation using SCET
techniques is based on factorisation theorems, and requires the
calculation of jet, soft and beam functions to some perturbative
accuracy. This task has up to now mainly been achieved analytically, on
a case-by-case basis.
To facilitate the resummation of global logarithms to NNLL accuracy, we
present a framework to numerically compute the two-loop soft function
for a general class of observables containing e.g. e+e-event shapes and
inclusive hadron collider observables. The algorithm has been
implemented in the publicly available program SoftSERVE, and is
currently limited to processes with two hard (coloured) directions. I
will present the general strategy of our approach, some new results for
event-shape and jet-grooming observables, as well as recent progress on
extending the setup to processes with more than two jet-like directions.