We outline the concrete steps involved in building prescriptive master integrand bases for scattering amplitudes beyond the planar limit. We highlight the role of contour choices in such bases, and illustrate the full process by constructing a complete, triangle power-counting basis at two loops for six particles. We show how collinear contour choices can be used to divide integrand bases into separately finite and divergent subspaces, and how double-poles can be used to further subdivide these spaces according to (transcendental) weight. Complete details of the basis constructed for six particles is provided in the ancillary files for this work's submission to the arXiv.
@article{arxiv.2112.05157,
title = {Illustrations of Integrand-Basis Building at Two Loops},
author = {Jacob L. Bourjaily and Cameron Langer and Yaqi Zhang},
journal= {arXiv preprint arXiv:2112.05157},
year = {2022}
}
Comments
39 pages; 2 tables; dozens of figures. Complete prescriptive basis for six particles is provided in ancillary files