The SISCone jet algorithm optimised for low particle multiplicities

The SISCone jet algorithm is a seedless infrared-safe cone jet algorithm. There exists an implementation which is highly optimised for a large number of final state particles. However, in fixed-order perturbative calculations with a small number of final state particles, it turns out that the computer time needed for the jet clustering of this implementation is comparable to the computer time of the matrix elements. This article reports on an implementation of the SISCone algorithm optimised for low particle multiplicities.Program summaryProgram title: siscone_partonCatalogue identifier: AELF_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AELF_v1_0.htmlProgram obtainable from: CPC Program Library, Queenʼs University, Belfast, N. IrelandLicensing provisions: GNU General Public License version 2No. of lines in distributed program, including test data, etc.: 1588No. of bytes in distributed program, including test data, etc.: 41 164Distribution format: tar.gzProgramming language: C++Computer: AllOperating system: AllRAM: Negligible for low parton multiplicities.Classification: 11.9Nature of problem: Clustering of particles into jets.Solution method: Infrared-safe cone algorithm.Restrictions: Hard-coded restriction to 64 final state particles on 64-bit machines, but recommended to be used only for configurations with up to 10 final state particles.Running time:   Depending on the number of final state particles, O(μs)O(μs) for configurations up to 5 final state particles.