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arXiv · 2506.07231

Towards numerical two-loop integrand reduction

Giuseppe Bevilacqua·Dhimiter Canko·Costas Papadopoulos·Aris Spourdalakis
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Abstract

We present a method for the integrand-level reduction of two-loop helicity amplitudes in both $d=4-2\epsilon$ and $d=4$ dimensions. The amplitude is expressed in terms of a set of Feynman integrals and their coefficients that depend on the external kinematics. The analysis presented in this paper, in conjunction with the ongoing development of the computational framework $\text{HELAC-2LOOP}$, paves the road for the construction of an automated program for two-loop amplitude calculations for arbitrary scattering processes.

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Giuseppe Bevilacqua, Dhimiter Canko, Costas Papadopoulos, Aris Spourdalakis. 2025-06-08. Towards numerical two-loop integrand reduction. https://arxiv.org/abs/2506.07231

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