Unitarity methods for Magnus amplitudes

Abstract

Magnus amplitudes refer to the matrix elements of the logarithm of the $S$-matrix. Modern unitarity methods construct cut-constructible parts of scattering amplitudes without directly invoking Feynman diagrams, offering an efficient way of obtaining loop integrands for scattering amplitudes. A procedure is presented that adapts unitarity methods to the computation of Magnus amplitudes.

arXiv comment7+2 pages, 14 figures