Tensor Loop Reduction via the Baikov Representation and an Auxiliary Vector

Liang Zhang

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arXiv · 2309.00930

Tensor Loop Reduction via the Baikov Representation and an Auxiliary Vector

Liang Zhang

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Abstract

In this paper, we introduce a simple and efficient approach for the general reduction of one-loop integrals. Our method employs the introduction of an auxiliary vector and the identification of the tensor structure as an auxiliary propagator. This key insight allows us to express a wide range of one-loop integrals, encompassing both tensor structures and higher poles, in the Baikov representation. By establishing an integral-by-parts (IBP) relation, we derive a recursive formula that systematically solves the one-loop reduction problem, even in the presence of various degenerate cases. Our proposed strategy is characterized by its simplicity and effectiveness, offering a significant advancement in the field of one-loop calculations.

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Liang Zhang. 2023-09-02. Tensor Loop Reduction via the Baikov Representation and an Auxiliary Vector. https://arxiv.org/abs/2309.00930

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