  We study primordial density perturbations generated by the late decay of a
curvaton field whose decay rate may be modulated by the local value of another
isocurvature field, analogous to models of modulated reheating at the end of
inflation. We calculate the primordial density perturbation and its local-type
non-Gaussianity using the sudden-decay approximation for the curvaton field,
recovering standard curvaton and modulated reheating results as limiting cases.
We verify the Suyama-Yamaguchi inequality between bispectrum and trispectrum
parameters for the primordial density field generated by multiple field
fluctuations, and find conditions for the bound to be saturated.
