Delta-N Formalism for Curvaton with Modulated Decay

Abstract

In this paper, the curvature perturbation generated by the modulated curvaton decay is studied by a direct application of $\delta N$-formalism. Our method has a sharp contrast with the {\it non-linear formalism} which may be regarded as an indirect usage of $\delta N$-formalism. We first show that our method can readily reproduce results in previous works of modulation of curvaton. Then we move on to calculate the case where the curvaton mass (and hence also the decay rate) is modulated. The method can be applied to the calculation of the modulation in the freezeout model, in which the heavy species are considered instead of the curvaton. Our method explains curvaton and various modulation on an equal footing.

13 pages, 2 figures, to appear in JCAP

References in corpus (4)

• CMB Constraints on Primordial non-Gaussianity from the Bispectrum (f_{NL}) and Trispectrum (g_{NL} and τ_{NL}) and a New Consistency Test of Single-Field Inflation
• Modulated curvaton decay
• Density Perturbations from Modulated Decay of the Curvaton
• Cosmological perturbations from an inhomogeneous phase transition

Cited by in corpus (4)

• Scale-dependent CMB asymmetry from primordial configuration
• Modulated decay in the multi-component Universe
• Thermal Inflation with a Thermal Waterfall Scalar Field Coupled to a Light Spectator Scalar Field
• Towards an analytic solution of rapid roll inflation with a quartic potential