A smooth version of the RS model

We study the physical properties of a thick brane solution arising in a 5D theory of gravity coupled to a bulk self‐interacting scalar field in a Riemannian manifold. By analyzing the graviton spectrum of this model, we find a particular case in which the 4D graviton is separated from the massive KK gravitons by a mass gap. In this case, the corresponding effective Schrodinger equation can be solved exactly and has a modified Poschl‐Teller potential. Apart from the massless 4D graviton, there is one massive KK bound state, and a continuum spectrum of delocalized KK modes. We discuss on the mass hierarchy problem and, finally, compute the corrections to Newton's law in the thin brane limit for this case.