Radion production in gamma-electron collisions
  We analyze the potential of Compact Linear Colliders based on the \gamma-e collisions to search for the radion in the Randall-Sundrum model, where compactification radius of the extra dimension is stabilized by the radion, which is a scalar field lighter than the graviton Kaluza-Klein states. The radion production in the high energy \gamma-e colliders with the polarization of the electron beams are calculated in detail. Numerical evaluation shows that if the radion mass is not too heavy with the mass order of GeV then the reaction can give observable cross section in future colliders at the high degree of polarization. 
D. V.Soa, T. D.Tham, N. H.Thao, D. T. L.Thuy
hep-ph