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arXiv 2011.133372020-11-26hep-phhep-th

Massive kite diagrams with elliptics

M. A. Bezuglov, A. I. Onishchenko, O. L. Veretin

备注：: 21 page, 4 figures
DOI：: 10.1016/j.nuclphysb.2020.115302

英文摘要：

We present the results for two-loop massive kite master integrals with elliptics in terms of iterated integrals with algebraic kernels. The key ingredients are new integral representations for sunset subgraphs in $d=4-2ε$ and $d=2-2ε$ dimensions together with differential equations for considered kite master integrals in $A+Bε$ form. The obtained results can be easily generalized to all orders in $ε$-expansion and show that the class of functions defined as iterated integrals with algebraic kernels may be large enough for writing down results for a large class of massive Feynman diagrams.

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