Hilltop Non-Gaussianity

Kawasaki, Masahiro; Nakayama, Kazunori; Takahashi, Fuminobu

Hilltop Non-Gaussianity

Authors

Kawasaki, Masahiro

Nakayama, Kazunori

Takahashi, Fuminobu

Description

We study non-Gaussianity induced by a pseudo Nambu-Goldstone boson with a cosine-type scalar potential. We focus on how the non-Gaussianity is affected when the pseudo Nambu-Goldstone boson rolls down from near the top of the scalar potential where the deviation from a quadratic potential is large. We find that the resultant non-Gaussianity is similar to that obtained in the quadratic potential, if the pseudo Nambu-Goldstone boson accounts for the curvature perturbation; the non-Gaussianity is enhanced, otherwise.
12 pages, 3 figures; References added; to appear in JCAP