Elsevier Science Home
Computer Physics Communications Program Library
Full text online from Science Direct
Programs in Physics & Physical Chemistry
CPC Home

[Licence| Download | New Version Template] aeir_v2_1.tar.gz(2447 Kbytes)
Manuscript Title: Massive non-planar two-loop four-point integrals with SecDec 2.1
Authors: Sophia Borowka, Gudrun Heinrich
Program title: SecDec 2.1
Catalogue identifier: AEIR_v2_1
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 184(2013)2552
Programming language: Wolfram Mathematica, Perl, Fortran/C++.
Computer: From a single PC to a cluster, depending on the problem.
Operating system: Unix, Linux.
RAM: Depends on the complexity of the problem
Keywords: Perturbation theory, Feynman diagrams, Multi-loop, numerical integration, Top quark pair production.
PACS: 12.38.Bx, 02.60.Jh, 02.70.Wz.
Classification: 4.4, 5, 11.1.

External routines: BASES [1], CUBA [2]. The codes for both are included in the SecDec 2.1 distribution file.

Does the new version supersede the previous version?: Yes

Nature of problem:
Extraction of ultraviolet and infrared singularities from parametric integrals appearing in higher order perturbative calculations in gauge theories. Numerical integration in the presence of integrable singularities (e.g. kinematic thresholds in massive multi-loop integrals). Flexibility to treat non-standard user defined functions

Solution method:
Algebraic extraction of singularities in dimensional regularisation using iterated sector decomposition. This leads to a Laurent series in the dimensional regularisation parameter ε, where the coefficients are finite integrals over the unit-hypercube. Those integrals are evaluated numerically by Monte Carlo integration. The integrable singularities are handled by choosing a suitable integration contour in the complex plane, in an automated way.

Reasons for new version:
Several improvements and new features.

Summary of revisions:
Extended tensor integral option, flexibility to evaluate non-standard loop integral functions and to skip primary decomposition step, improvements in the user interface and the error treatment.

Depending on the complexity of the problem, limited by CPU time or memory.

Running time:
Between a few minutes and several days, depending on the complexity of the problem.

[1] S. Kawabata, A New version of the multidimensional integration and event generation package BASES/SPRING, Comput. Phys. Commun. 88(1995)309.
[2] T. Hahn, CUBA: A Library for multidimensional numerical integration, Comput. Phys. Commun. 168(2005)78