External leg corrections in the unitarity method
High Energy Physics - Phenomenology
2015-05-30 v2 High Energy Physics - Theory
Abstract
Unitarity cuts diverge in the channel of a single massive external fermion. We propose an off-shell continuation of the momentum that allows a finite evaluation of the unitarity cuts. If the cut is taken with complete amplitudes on each side, our continuation and expansion around the on-shell configuration produces the finite contribution to the bubble coefficient. Finite parts in the expansion of the external leg counterterms must be included explicitly as well.
Cite
@article{arxiv.1109.5106,
title = {External leg corrections in the unitarity method},
author = {Ruth Britto and Edoardo Mirabella},
journal= {arXiv preprint arXiv:1109.5106},
year = {2015}
}
Comments
28 pages, 9 figures. Published version. Eq. (B.17) corrected, minor clarifications, typos fixed