One-Loop Yang-Mills Integrands from Scattering Equations

We investigate in the context of the scattering equations, how one-loop linear propagator integrands in gauge theories can be linked to integrands with quadratic propagators using a double forward limit. We illustrate our procedure through examples and demonstrate how the different parts of the derived quadratic integrand are consistent with cut-integrands derived from four-dimensional generalized unitarity. We also comment on applications and discuss possible further generalizations.Comment: 20 pages, 6 figures, typos corrected, added clarifications and comments. Version to be published in PR