CHY representations for gauge theory and gravity amplitudes with up to three massive particles

TL;DR

This paper demonstrates that a broad class of tree-level scattering amplitudes involving up to three massive particles can be represented using CHY formulas, revealing their mass independence and similarity to massless amplitudes.

Contribution

It extends CHY representations to include amplitudes with up to three massive particles, showing their equivalence to massless amplitudes when expressed in suitable invariants.

Findings

Amplitudes with up to three massive particles are expressible via CHY formulas.

These amplitudes are mass-independent when written in appropriate kinematic variables.

The results unify massive and massless amplitude descriptions within the CHY framework.

Abstract

We show that a wide class of tree-level scattering amplitudes involving scalars, gauge bosons, and gravitons, up to three of which may be massive, can be expressed in terms of a Cachazo-He-Yuan representation as a sum over solutions of the scattering equations. These amplitudes, when expressed in terms of the appropriate kinematic invariants, are independent of the masses and therefore identical to the corresponding massless amplitudes.