Cosmological parameters and the redshift distribution of gravitational lenses.
Abstract
For known gravitational lens systems the redshift distribution of the lenses is compared with theoretical expectations for 10^4^ FriedmannLemaitre cosmological models, which more than cover the range of possible cases. The comparison is used for assigning a relative probability to each of the models. The entire procedure is repeated for different values of the inhomogeneity parameter η and the limiting spectroscopic magnitude m_lim_, which is important for selection effects. The dependence on these two parameters is examined in more detail for the special cases λ_0_=0 and k=0. Previous results that this method is a better probe for λ_0_ than {OMEGA}_0_ are confirmed, but it appears that the low probability of models with large λ_0_ values found using similar methods is due to a selection effect. The power of this method to discriminate between cosmological models can of course be improved if more gravitational lens systems are found. However, our numerical simulations indicate that a reasonable number of observed systems cannot deliver interesting constraints on the cosmological parameters.
 Publication:

Astronomy and Astrophysics
 Pub Date:
 April 1996
 arXiv:
 arXiv:astroph/9501013
 Bibcode:
 1996A&A...308..359H
 Keywords:

 GRAVITATIONAL LENSING;
 COSMOLOGY: THEORY;
 COSMOLOGY: OBSERVATIONS;
 Astrophysics
 EPrint:
 One selfunpacking uuencoded compressed PostScript file (created with uufiles) containing the complete text with all figures included (here 140kb gzipped, unpacked 975kb). 10 pages. Should be printable without loss on USsize paper. Paper version available on request. Changesnothing removed, typos corrected, the following additions: one figure, one table and some text explaining the structure in the plots in more detail