Abstract
We present a new method for computing complete one-loop amplitudes, including their rational parts, in nonsupersymmetric gauge theory. This method merges the unitarity method with on-shell recursion relations. It systematizes a unitarity-factorization bootstrap approach previously applied by the authors to the one-loop amplitudes required for next-to-leading order QCD corrections to the processes jets and jets. We illustrate the method by reproducing the one-loop color-ordered five-gluon helicity amplitudes in QCD that interfere with the tree amplitude, namely and . Then we describe the construction of the six- and seven-gluon amplitudes with two adjacent negative-helicity gluons, and , which uses the previously-computed logarithmic parts of the amplitudes as input. We present a compact expression for the six-gluon amplitude. No loop integrals are required to obtain the rational parts.
1 More- Received 25 August 2005
DOI:https://doi.org/10.1103/PhysRevD.73.065013
©2006 American Physical Society