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[Licence| Download | New Version Template] aecp_v1_0.tar.gz(6009 Kbytes)
Manuscript Title: Feynman Integral Evaluation by a Sector decomposiTion Approach (FIESTA)
Authors: A.V. Smirnov, M.N. Tentyukov
Program title: FIESTA
Catalogue identifier: AECP_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 180(2009)735
Programming language: Wolfram Mathematica 6.0 [3] and C.
Computer: from a desktop PC to supercomputer.
Operating system: Unix, Linux, Windows.
RAM: depends on the complexity of the problem
Keywords: Feynman diagrams, Sector decomposition, Numerical integration, Data-driven evaluation.
PACS: 02.60.Jh, 02.70.Wz, 11.10.Gh.
Classification: 4.4, 4.12, 5, 6.5.

External routines: QLink [1], Vegas [2]

Nature of problem:
The sector decomposition approach to evaluating Feynman integrals falls apart into the sector decomposition itself, where one has to minimize the number of sectors; the pole resolution and epsilon expansion; and the numerical integration of the resulting expression.

Solution method:
The sector decomposition is based on a new strategy. The sector decomposition, pole resolution and epsilon-expansion are performed in Wolfram Mathematica 6.0 [3]. The data is stored on hard disk via a special program, QLink [1]. The expression for integration is passed to the C-part of the code, that parses the string and performs the integration by the Vegas algorithm [2]. This part of the evaluation is perfectly parallelized on multi-kernel computers.

Restrictions:
The complexity of the problem is mostly restricted by the CPU time required to perform the evaluation of the integral, however there is currently a limit of maximum 11 positive indices in the integral; this restriction is to be removed in future versions of the code.

Additional comments:
The program works successfully with a single processor, however, it is ready to work in a parallel environment, and the use of multi-kernel processor and multi-processor computers significantly speeds up the calculation.

Running time:
depends on the complexity of the problem.

References:
[1] http://qlink08.sourceforge.net, open source
[2] G. P. Lepage, the Cornell preprint CLNS-80/447,1980.
[3] http://www.wolfram.com/products/mathematica/index.html