Production and decay of radion in Randall-Sundrum model at a photon collider.

A warped extra dimension model predicts an extra scalar particle beyond the Standard Model (SM) which is called a radion. Although interactions of the radion are similar to those of the Higgs boson in the SM, a relatively light radion (< 100 GeV) is not severely constrained from the Higgs search experiments at the LHC. In this paper we study discovery potential of the radion at a photon collider as an option of ILC. Owing to the trace anomaly of the energy-momentum tensor, both a production of radion in 7 7 collision and its decay to gluon pair are enhanced sizably. We find that the photon collider has a sensitivity for discovering the radion in low-mass region up to Aw, ~ 3 TeV, where A, is a scale parameter which suppresses the interactions of radion to the SM particles. [ABSTRACT FROM AUTHOR]