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.
|Journal||Journal of Cosmology and Astroparticle Physics|
|Publication status||Published - 2009|
- Cosmology of theories beyond the SM
- Physics of the early universe
ASJC Scopus subject areas
- Astronomy and Astrophysics