Randall-Sundrum Phenomenology at Linear Colliders
Thomas G Rizzo · 2000
Abstract. The physics of the Randall-Sundrum model relevant for future linear colliders is briefly summarized. The differences between the case where Standard Model(SM) fields are on the wall and where they are in the bulk are emphasized. Randall and Sundrum(RS) [1] have recently proposed a novel approach in dealing with the hierarchy problem wherein an exponential warp factor arises from a 5-d non-factorizable geometry based on a slice of AdS5 space. Here, two 3-branes sit at the orbifold fixed points y = 0 (Plank brane) and y = πrc (SM or TeV brane) with equal and opposite tensions with the AdS5 space between them. The model contains no large parameter hierarchies with MPl, the 5-d Planck scale, M5, and the AdS curvature parameter, k, being of qualitatively similar magnitudes. TeV scales can be generated on the brane at y = πrc if gravity is localized on the other brane and krc ≃ 11 − 12; indeed in this case the scale of physical processes on the SM brane is found to be given by Λπ = MPle −krcπ which is of order a TeV. Such a model leads to very interesting and predictive phenomenology that can be explored in detail at colliders [2]. In the simplest scenario the SM fields are constrained to lie on the TeV brane while gravitons can propagate in the bulk in which case only two parameters are necessary to describe the model: c = k/MPl, which is expected to be near though somewhat less than unity, and m1 = kx1e −krcπ, which is the mass of the first graviton Kaluza-Klein excitation. The masses of the