Celestial superamplitudes

We study celestial amplitudes in (super) Yang-Mills theory using a parametrization of the spinor helicity variables where their overall phase is not fixed by the little group action. In this approach the spin constraint h - (h) over bar = J for celestial conformal primaries emerges naturally from a new Mellin transform, and the action of conformal transformations on celestial amplitudes is derived. Applying this approach to N = 4 super Yang-Mills, we show how the appropriate definition of on-shell superspace coordinates leads naturally to a formulation of chiral celestial superamplitudes and a representation of the generators of the four-dimensional superconformal algebra on the celestial sphere, which by construction annihilate all tree-level celestial superamplitudes.

Automated summary

In this study, celestial amplitudes in (super) Yang-Mills theory are investigated using a parametrization of spinor helicity variables that allows for an unfixed overall phase. A new Mellin transform naturally yields the spin constraint h - (h) over bar = J for celestial conformal primaries, and the conformal transformation of celestial amplitudes is derived. The approach is applied to N = 4 super Yang-Mills, demonstrating the formulation of chiral celestial superamplitudes and the representation of generators of the four-dimensional superconformal algebra on the celestial sphere, which annihilate all tree-level celestial superamplitudes.