arXiv 0712.21032007-12-18hep-phastro-phhep-th

Hilltop Curvatons

Tomohiro Matsuda

备注：: 15 pages, added references
发表信息：: Phys.Lett.B659:783-788,2008
DOI：: 10.1016/j.physletb.2007.12.008

英文摘要：

We study ``hilltop'' curvatons that evolve on a convex potential. Hilltop curvatons evolving on the Hubble-induced potential are generic if supergravity is assumed in the theory. We do not consider curvatons whose potential is protected from $O(H)$ corrections, where $H$ is the Hubble parameter. We assume that the effective mass of a curvaton is expressed as $m_σ= c H$, where the coefficient varies within $0.2 \le c \le 5$ depending on the circumstances. A negative mass term may lead to enhancement of curvaton fluctuation, which has a significant impact on the energy bound for low-scale inflation. Using a simple curvaton model and following the conventional curvaton hypothesis, we demonstrate the generality of this enhancement.

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