Phenomenology of the radion in the Randall-Sundrum scenario at colliders

Phenomenology of a radion (phi) that stabilizes the modulus in the Randall- Sundrum scenario is considered. The radion couples to the trace of energy m omentum tensor of the standard model (SM) with a strength suppressed only b y a new scale (Lambda(phi)) of an order of the electroweak scale. In partic ular, the effective coupling of a radion to two gluons is enhanced due to t he trace anomaly of QCD. Therefore, its production cross section at hadron colliders could be enhanced, and the dominant decay mode of a relatively li ght radion is phi --> gg, unlike the SM Higgs boson case. We also present c onstraints on the mass m(phi) and the new scale Lambda(phi) from the Higgs search limit at LEP and perturbative unitarity bound. (C) 2000 Elsevier Sci ence B.V. All rights reserved.