Dynamical Radion Superfield in Five-dimensional Action

TL;DR

This paper systematically derives the 5D N=1 superspace action incorporating a dynamical radion superfield, clarifying its couplings and mass, based on superconformal supergravity.

Contribution

It provides a systematic derivation of the radion superfield dependence in 5D superspace action using superconformal supergravity.

Findings

Radion appears with correct mode function in the action.

Couplings of radion superfield to matter are explicitly derived.

Radion mass can be accurately calculated from the superspace action.

Abstract

We clarify the radion superfield dependence of 5D N=1 superspace action. The radion is treated as a dynamical field and appears in the action with the correct mode function. Our derivation is systematic and based on the superconformal formulation of 5D supergravity. We can read off the couplings of the dynamical radion superfield to the matter superfields from our result. The correct radion mass can be obtained by calculating the radion potential from our superspace action.