Revised $f_{\rm NL}$ parameter in Curvaton Scenario

Understand

We revise the Non-Gaussianity of canonical curvaton scenario with a generalized $\delta N$ formalism, in which it could handle the generic potentials.

• In various curvaton models, the energy density is dominant in different period including the secondary inflation of curvaton, matter domination and radiation domination.
• Our method could unify to deal with these periods since the non-linearity parameter $f_{\rm NL}$ associated with Non-Gaussianity is a function of equation of state $w$.
• We firstly investigate the most simple curvaton scenario, namely the chaotic curvaton with quadratic potential.