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arXiv · 2105.10263

Celestial Superamplitudes

Andreas Brandhuber·Graham R. Brown·Joshua Gowdy·Bill Spence·Gabriele Travaglini
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Abstract

We study celestial amplitudes in (super) Yang-Mills theory using a parameterisation of the spinor helicity variables where their overall phase is not fixed by the little group action. In this approach the spin constraint $h-\bar{h}=J$ 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 $\mathcal{N}\!=\!4$ 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.

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Andreas Brandhuber, Graham R. Brown, Joshua Gowdy, Bill Spence, Gabriele Travaglini. 2021-05-21. Celestial Superamplitudes. https://doi.org/10.1103/physrevd.104.045016

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