English

Physical projectors for multi-leg helicity amplitudes

High Energy Physics - Phenomenology 2019-09-04 v1 High Energy Physics - Theory

Abstract

We present a method for building physical projector operators for multi-leg helicity amplitudes. For any helicity configuration of the external particles, we define a physical projector which singles out the corresponding helicity amplitude. For processes with more than four external legs, these physical projectors depend on significantly fewer tensor structures and exhibit a remarkable simplicity compared with projector operators defined with traditional approaches. As an example, we present analytic formulas for a complete set of projectors for five-gluon scattering. These have been validated by reproducing known results for five-gluon amplitudes up to one-loop.

Cite

@article{arxiv.1906.03298,
  title  = {Physical projectors for multi-leg helicity amplitudes},
  author = {Tiziano Peraro and Lorenzo Tancredi},
  journal= {arXiv preprint arXiv:1906.03298},
  year   = {2019}
}

Comments

18 pages

R2 v1 2026-06-23T09:47:26.421Z