Distributed and multi-core computation of 2-loop integrals

15th International Workshop on Advanced Computing and Analysis Techniques in Physics Research

物理学;计算机科学

De Doncker, E.^1 ; Yuasa, F.^2

Department of Computer Science, Western Michigan University, Kalamazoo, MI 49008, United States^1

High Energy Accelerator Research Organization (KEK), Oho 1-1, Ibaraki, 305-0801 Tsukuba, Japan^2

关键词: Adaptive integration methods;    Automatic computations;    Extrapolation techniques;    Feynman loop integrals;    Integral approximation;    Integral transformations;    Parallel implementations;    Parallel performance;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/523/1/012052/pdf
DOI  :  10.1088/1742-6596/523/1/012052

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

For an automatic computation of Feynman loop integrals in the physical region we rely on an extrapolation technique where the integrals of the sequence are obtained with iterated/repeated adaptive methods from the QUADPACK 1D quadrature package. The integration rule evaluations in the outer level, corresponding to independent inner integral approximations, are assigned to threads dynamically via the OpenMP runtime in the parallel implementation. Furthermore, multi-level (nested) parallelism enables an efficient utilization of hyperthreading or larger numbers of cores. For a class of loop integrals in the unphysical region, which do not suffer from singularities in the interior of the integration domain, we find that the distributed adaptive integration methods in the multivariate PARINT package are highly efficient and accurate. We apply these techniques without resorting to integral transformations and report on the capabilities of the algorithms and the parallel performance for a test set including various types of two-loop integrals.