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arXiv · hep-ph/0207091

Special case of sunset: reduction and epsilon-expansion

A. Onishchenko·O. Veretin
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Abstract

We consider two loop sunset diagrams with two mass scales m and M at the threshold and pseudotreshold that cannot be treated by earlier published formula. The complete reduction to master integrals is given. The master integrals are evaluated as series in ratio m/M and in epsilon with the help of differential equation method. The rules of asymptotic expansion in the case when q^2 is at the (pseudo)threshold are given.

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A. Onishchenko, O. Veretin. 2002-07-05. Special case of sunset: reduction and epsilon-expansion. https://doi.org/10.1134/1.2011500

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