Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2008-10-16
JHEP 0812:067,2008
Physics
High Energy Physics
High Energy Physics - Theory
31 pages, JHEP3 class, 10 figures
Scientific paper
10.1088/1126-6708/2008/12/067
We show that one-loop amplitudes in massless gauge theories can be determined from single cuts. By cutting a single propagator and putting it on-shell, the integrand of an n-point one-loop integral is transformed into an (n+2)-particle tree level amplitude. The single-cut approach described here is complementary to the double or multiple unitarity cut approaches commonly used in the literature. In common with these approaches, if the cut is taken in four dimensions, one finds only the cut-constructible parts of the amplitude, while if the cut is in D=4-2 epsilon dimensions, both rational and cut-constructible parts are obtained. We test our method by reproducing the known results for the fully rational all-plus and mostly-plus QCD amplitudes A^{(1)}_4(1^+,2^+,3^+,4^+) and A^{(1)}_5(1^+,2^+,3^+,4^+,5^+). We also rederive expressions for the scalar loop contribution to the four-gluon MHV amplitude, A_4^{(1,N=0)}(-,-,+,+) which has both cut-constructible and rational contributions, and the fully cut-constructible n-gluon MHV amplitude in N=4 Supersymetric Yang-Mills, A_4^{(1,N=4)}(-,-,+,...,+).
Nigel Glover E. W.
Williams Ciaran
No associations
LandOfFree
One-Loop Gluonic Amplitudes from Single Unitarity Cuts does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with One-Loop Gluonic Amplitudes from Single Unitarity Cuts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and One-Loop Gluonic Amplitudes from Single Unitarity Cuts will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-368299