Non-Gaussianity and gravitational wave background in curvaton with a
  double well potential
  We study the density perturbation by a curvaton with a double well potential
and estimate the nonlinear parameters for non-Gaussianity and the amplitude of
gravitational wave background generated during inflation. The predicted
nonlinear parameters strongly depend on the size of a curvaton self-coupling
constant as well as the reheating temperature after inflation for a given
initial amplitude of the curvaton. The difference from usual massive
self-interacting curvaton is also emphasized.
