arXiv:hep-ph/0407094·v1·High Energy Physics — Phenomenology
Two-loop Splitting Amplitudes
Z. Bern🇺🇸 · L.J. Dixon🇺🇸 · D.A. Kosower🇫🇷
Abstract
Splitting amplitudes govern the behavior of scattering amplitudes at the momenta of external legs become collinear. In this talk we outline the calculation of two-loop splitting amplitudes via the unitarity sewing method. This method retains the simple factorization properties of light-cone gauge, but avoids the need for prescriptions such as the principal value or Mandelstam-Leibbrandt ones. The encountered loop momentum integrals are then evaluated using integration-by-parts and Lorentz invariance identities. We outline a variety of applications for these splitting amplitudes.
Comments: Contribution to the Proceedings of "Loops and Legs in Quantum Field Theory 2004", Zinnowitz, Usedom Island, Germany, April 2004. 5 pages, latex, espcrc2, 5 figures