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Constraints on h, and from cosmic microwave background observations
Charles H. Lineweaver 1,
Domingos Barbosa 1, 2,
Alain Blanchard 1 and
James G. Bartlett 1
Received 1 August 1996 / Accepted 25 October 1996
In this paper we compare data to theory. We use a compilation of the most recent cosmic microwave background (CMB) measurements to constrain Hubble's constant h, the baryon fraction , and the cosmological constant . We fit h -, - and -dependent power spectra to the data. The models we consider are flat cold dark matter (CDM) dominated universes with flat () power spectra, thus the results obtained apply only to these models. CMB observations can exclude more than half of the parameter space explored. The CMB data favor low values of Hubble's constant; . Low values of are preferred () but the minimum is shallow and we obtain . A model with , and is permitted by constraints from the CMB data, BBN, cluster baryon fractions and the shape parameter derived from the mass density power spectra of galaxies and clusters.
For flat- models, the CMB data, combined with BBN constraints exclude most of the plane. Models with , with are fully consistent with the CMB data but are excluded by the strict new limits from supernovae (Perlmutter et al. 1997). A combination of CMB data goodness-of-fit statistics, BBN and supernovae constraints in the plane, limits Hubble's constant to the interval .
Key words: cosmic microwave background cosmology: observations; theory
Send offprint requests to: Charley Lineweaver, email@example.com
© European Southern Observatory (ESO) 1997
Online publication: June 5, 1998