Eur. Phys. J. C (2012) 72: 1929
https://doi.org/10.1140/epjc/s10052-012-1929-x

Special Article - Tools for Experiment and Theory

ExSample—a library for sampling Sudakov-type distributions

DESY, Notkestrasse 85, 22607, Hamburg, Germany

^* e-mail: simon.plaetzer@desy.de

Received: 13 September 2011
Revised: 10 February 2012
Published online: 13 March 2012

Abstract

Sudakov-type distributions are at the heart of generating radiation in parton showers as well as contemporary NLO matching algorithms along the lines of the POWHEG algorithm. In this paper, the C++ library ExSample is introduced, which implements adaptive sampling of Sudakov-type distributions for splitting kernels which are in general only known numerically. Besides the evolution variable, the splitting kernels can depend on an arbitrary number of other degrees of freedom to be sampled, and any number of further parameters which are fixed on an event-by-event basis.