MASSIVE LOOP AMPLITUDES FROM UNITARITY

@article{Bern1996MASSIVELA,
  title={MASSIVE LOOP AMPLITUDES FROM UNITARITY},
  author={Zvi Bern and A. G. Morgan},
  journal={Nuclear Physics},
  year={1996},
  volume={467},
  pages={479-509}
}

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References

SHOWING 1-10 OF 99 REFERENCES
Multigluon helicity amplitudes involving a quark loop.
  • Mahlon
  • Physics
    Physical review. D, Particles and fields
  • 1994
We apply the solution to the recursion relation for the double-off-shell quark current to the problem of computing one loop amplitudes with an arbitrary number of gluons. We are able to compute
Efficient calculation of one-loop QCD amplitudes.
TLDR
The outline of a new and efficient technique for the calculation of loop amplitudes in a gauge theory based on the technology of four-dimensional heterotic strings is presented, which finds complete agreement with the previous Feynman-diagram calculation of Ellis and Sexton.
Supersymmetry relations between contributions to one-loop gauge boson amplitudes.
  • Bern, Morgan
  • Physics
    Physical review. D, Particles and fields
  • 1994
TLDR
The ideas motivated by string theory are applied to improve the calculational efficiency of one-loop weak interaction processes with massive external gauge bosons and supersymmetry relations between diagrams with a fermion loop and with a gauge boson loop hold are illustrated.
One-loop n-gluon amplitudes with maximal helicity violation via collinear limits.
TLDR
A conjecture is presented that the corresponding amplitudes where three or more gluon legs are replaced by photons vanish for [ital n][gt]4.
...
...