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arXiv · hep-ph/0509181

Differential equations and high-energy expansion of two--loop diagrams in D dimensions

A. V. Bogdan·R. N. Lee
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Abstract

New method of calculation of master integrals using differential equations and asymptotical expansion is presented. This method leads to the results exact in space-time dimension $D$ having the form of the convergent power series. As an application of this method, we calculate the two--loop master integral for "crossed--triangle" topology which was previously known only up to $O(\ep)$ order. The case when a topology contains several master integrals is also considered. We present an algorithm of the term-by-term calculation of the asymptotical expansion in this case and analyze in detail the "crossed--box" topology with three master integrals.

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A. V. Bogdan, R. N. Lee. 2005-10-18. Differential equations and high-energy expansion of two--loop diagrams in D dimensions. https://doi.org/10.1016/j.nuclphysb.2005.10.024

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