Scale-dependence of non-Gaussianity in the curvaton model

We investigate the scale-dependence of f(NL) in the self-interacting curvaton model. We show that the scale-dependence, encoded in the spectral index n(fNL), can be observable by future cosmic microwave background observations, such as CMBpol, in a significant part of the parameter space of the model. We point out that together with information about the trispectrum g(NL), the self-interacting curvaton model parameters could be completely fixed by observations. We also discuss the scale-dependence of g(NL) and its implications for the curvaton model, arguing that it could provide a complementary probe in cases where the theoretical value of n(fNL) is below observational sensitivity.