COBE-DMR constraints on a inflation model with non-minimal scalar field
  We derive the power spectra of the scalar- and tensor-type structures generated in a chaotic-type inflation model based on non-minimally coupled scalar field with a self interaction. By comparing contributions of both-structures to the anisotropy of the cosmic microwave background radiation with the four-year COBE-DMR data on quadrupole anisotropy we derive constraints on the ratio of self-coupling and non-minimal coupling constants, and the expansion rate in the inflation era, Eq. (12). The requirement of successful amount of inflation further constrains the relative amount of tensor-type contribution, Eq. (16). 
J. Hwang and H. Noh