Omega from the COBE-DMR anisotropy maps

We have made a likelihood statistical analysis of the angular correlations in the COBE-DMR two-year sky maps by Monte Carlo simulation of the temperature fluctuations. We assume an open universe and consider the primordial power spectrum of Harrison-Zeldovich, P(k) = Ak. We find that the flatness of the universe is not implied by the data. The quadrupole normalization amplitude, Q(rms-PS), is related to the density parameter, Omega, by Omega(rms-PS) = 10.67 + 55.81 Omega - 2128.59 Omega(2) + + 81.26 Omega(3) mu K. We have determined the probability distribution function (pdf) of Omega arising from cosmic plus sampling (i.e. 20 degrees galactic cut) variance which generically shows a bimodal shape. The uncertainty as given by the rms is approximate to 0.35; therefore, to constrain Omega better, experiments sensitive to higher multipoles (l > 20) should be considered.