Radion Couplings to Bulk Fields in the Randall-Sundrum Model
  The radion may be the lightest new state present in the Randall-Sundrum(RS) model. We examine the couplings of the radion to the Standard Model(SM) fields in the scenario where they propagate in the bulk and expand into Kaluza-Klein towers. These couplings are then contrasted with those of the more familiar case where the SM fields are confined to the TeV brane. We find that the couplings of the radion to both $gg$ and $\gamma\gamma$ can be significantly different in these two cases. Implications for radion collider phenomenology are discussed. 
Thomas G. Rizzo