Helicity Amplitudes for massive gravitinos in N=1 Supergravity

TL;DR

This paper develops methods to compute helicity amplitudes for massive gravitinos in N=1 supergravity, enabling detailed analysis of their interactions and decay processes.

Contribution

It introduces formal tools for constructing helicity amplitudes for massive gravitinos, including solutions to the Rarita-Schwinger equation and their application to decay and scattering calculations.

Findings

Calculated decay width for chi_0 -> gamma G

Derived cross sections for e+ e- -> GG

Demonstrated the effectiveness of the helicity amplitude methods

Abstract

We develop the formal tools needed to construct helicity amplitudes for massive gravitino in N=1 SUGRA. We start by considering the helicity states for massive spin-3/2 particles, which involves the solutions of Rarita-Schwinger equation. These solutions are written in terms of the helicity bra-ket notation and are used then to derive the interactions of gravitino with matter and gauge supermultiplets within N=1 Supergravity. The corresponding interactions of goldstinos are discussed too, relying on the goldstino-gravitino equivalence theorem. Finally to appreciate the power of our methods we evaluate the decay width chi_0 -> \gamma G, as well as the cross sections for e^+ e- -> GG.