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arXiv · 2007.00507

Reduction of Feynman Integrals in the Parametric Representation III: Integrals with Cuts

Wen Chen
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Abstract

Phase space cuts are implemented by inserting Heaviside theta functions in the integrands of momentum-space Feynman integrals. By directly parametrizing theta functions and constructing integration-by-parts (IBP) identities in the parametric representation, we provide a systematic method to reduce integrals with cuts. Since the IBP method is available, it becomes possible to evaluate integrals with cuts by constructing and solving differential equations.

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Wen Chen. 2020-07-01. Reduction of Feynman Integrals in the Parametric Representation III: Integrals with Cuts. https://doi.org/10.1140/epjc%2Fs10052-020-08757-3

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