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arXiv · 2601.17381

The calculation of 2-loop self-energy diagrams by the sector decomposition

Kiyoshi Kato
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Abstract

Detailed description of the calculation of the 2-loop self-energy for a scalar particle is presented. By employing a simple sector decomposition method, the ultraviolet divergent part is efficiently separated from the finite part. The resulting expression can be used for both analytic and numerical computation to renormalize the divergence and to provide finite results for physics.

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Kiyoshi Kato. 2026-01-24. The calculation of 2-loop self-energy diagrams by the sector decomposition. https://doi.org/10.57377/0002002705

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