Kinematically Blocked Curvaton

Abstract

In this paper, we investigate the idea that the decay of a curvaton is kinematically blocked and show that the coupling constant for curvaton decay can be as large as $\mathcal{O}(1)$. We also find in this case the lower bound of the Hubble parameter at horizon exit from big bang nucleosynthesis (BBN) is $H_{\ast }\text{gae}7.2\times 10^{-9}{M}_P\sim 10^{10}GeV$. Similar to conventional curvaton scenario, the nonlinear parameter can be as large as $f_{NL}=100$.

Comments: 6 pages, 2 figures, 2 tables; typos corrected, accepted for publication in MPLA