All tree-level amplitudes in massless QCD

Oct, 2010
40 pages
Published in:
  • JHEP 01 (2011) 035
e-Print:
Report number:
  • CERN-PH-TH-2010-230,
  • SLAC-PUB-14278,
  • HU-EP-10-57

Citations per year

20102014201820222024051015
Abstract: (arXiv)
We derive compact analytical formulae for all tree-level color-ordered gauge theory amplitudes involving any number of external gluons and up to three massless quark-anti-quark pairs. A general formula is presented based on the combinatorics of paths along a rooted tree and associated determinants. Explicit expressions are displayed for the next-to-maximally helicity violating (NMHV) and next-to-next-to-maximally helicity violating (NNMHV) gauge theory amplitudes. Our results are obtained by projecting the previously-found expressions for the super-amplitudes of the maximally supersymmetric Yang-Mills theory (N=4 SYM) onto the relevant components yielding all gluon-gluino tree amplitudes in N=4 SYM. We show how these results carry over to the corresponding QCD amplitudes, including massless quarks of different flavors as well as a single electroweak vector boson. The public Mathematica package GGT is described, which encodes the results of this work and yields analytical formulae for all N=4 SYM gluon-gluino trees. These in turn yield all QCD trees with up to four external arbitrary-flavored massless quark-anti-quark-pairs.
  • QCD Phenomenology
  • supersymmetry: 4
  • helicity: violation
  • quantum chromodynamics: massless
  • Yang-Mills: supersymmetry
  • quark: massless
  • quantum chromodynamics: scattering amplitude
  • higher-order: 0
  • fermion: flavor
  • gluino