Tests for cosmic dark matter from COBE
Abstract
We test models for the cosmic inhomogeneity spectrum based on cold dark matter against the angular correlation function, the statistics of temperature maxima and minima and the quadrupole amplitude in COBE-DMR maps. We show that while pure CDM and shallow CDM + string models are not completely consistent with COBE's data, steeper spectra provided by texture or isocurvature models pass the correlation-function and peak-number tests for practically any value of the cosmic density parameter including Ω 0 = 1 . CDM + texture models with Ω 0 ⋍ 0.7 also allow to reduce the well-known quadrupole discrepancy, and provide good fits with the best bias factor favored by recent measurement and a Hubble constant H 0 ⋍ 70 km s -1 Mpc -1 for the resulting value of Ω 0h they also agree with the properties of galaxy distributions. We suggest that a spectrum like the texture one and steeper than pure CDM can link the 10 Mpc and 10 3 Mpc regions and solve the problems of the cold matter scenario.
- Publication:
-
Astroparticle Physics
- Pub Date:
- December 1996
- DOI:
- 10.1016/S0927-6505(96)00039-4
- Bibcode:
- 1996APh.....6...25F