On classification of models of large local-type non-Gaussianity

We classify models generating large local-type non-Gaussianity into some categories by using some consistency relations among the non-linearity parameters f(NL)(local) , tau(local)(NL) and g(NL)(local) , which characterize the size of bispectrum for the former and trispectrum for the latter two. Then we discuss how one can discriminate models of large local-type non-Gaussianity with such relations. We first classify the models by using the ratio of tau(local)(NL)/( 6f(NL)(local)/5)(2), which is unity for single-source models and deviates from unity for multi-source ones. We can make a further classification of models in each category by utilizing the relation between f(NL)(local) and g(NL)(local) . Our classification suggests that observations of trispectrum would be very helpful to distinguish models of large non-Gaussianity and may reveal the generation mechanism of primordial fluctuations.