D-dimensional unitarity cut method
High Energy Physics - Phenomenology
2008-11-26 v2 High Energy Physics - Theory
Abstract
We develop a unitarity method to compute one-loop amplitudes with massless propagators in d=4-2*epsilon dimensions. We compute double cuts of the loop amplitudes via a decomposition into a four-dimensional and a -2*epsilon-dimensional integration. The four-dimensional integration is performed using spinor integration or other efficient techniques. The remaining integral in -2*epsilon dimensions is cast in terms of bubble, triangle, box, and pentagon master integrals using dimensional shift identities. The method yields results valid for arbitrary values of epsilon.
Cite
@article{arxiv.hep-ph/0609191,
title = {D-dimensional unitarity cut method},
author = {Charalampos Anastasiou and Ruth Britto and Bo Feng and Zoltan Kunszt and Pierpaolo Mastrolia},
journal= {arXiv preprint arXiv:hep-ph/0609191},
year = {2008}
}
Comments
4 pages. v2: references changed