Omega from the COBE-DMR anisotropy maps
Abstract
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, Ωrms-PS, is related to the density parameter, Ω, by Ωrms-PS=10.67+55.81Ω-128.59Ω2+81.26ω3 μK. We have determined the probability distribution function (pdf) of Ω arising from cosmic plus sampling (i.e. 20° galactic cut) variance which generically shows a bimodal shape. The uncertainty as given by the rms is ≈0.35; therefore, to constrain ωbetter, experiments sensitive to higher multipoles (l>20) should be considered.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 1996
- DOI:
- 10.1093/mnras/279.4.1095
- arXiv:
- arXiv:astro-ph/9507015
- Bibcode:
- 1996MNRAS.279.1095C
- Keywords:
-
- methods: data analysis -- cosmic microwave background -- cosmology: observations;
- Astrophysics
- E-Print:
- 4 pages, 2 figures, 1 table, uuencoded encapsulated postscript file. Figure 2 available upon request