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Constraints on Cosmological Parameters from the Analysis of the Cosmic Lens All Sky Survey Radio-Selected Gravitational Lens Statistics

K. -H. Chae·A. D. Biggs·R. D. Blandford·I. W. A. Browne·A. G. de Bruyn·C. D. Fassnacht·P. Helbig·N. J. Jackson·L. J. King·L. V. E. Koopmans·S. Mao·D. R. Marlow·J. P. McKean·S. T. Myers·M. Norbury·T. J. Pearson·P. M. Phillips·A. C. S. Readhead·D. Rusin·C. M. Sykes·P. N. Wilkinson·E. Xanthopoulos·T. York
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Abstract

We derive constraints on cosmological parameters and the properties of the lensing galaxies from gravitational lens statistics based on the final Cosmic Lens All Sky Survey (CLASS) data. For a flat universe with a classical cosmological constant, we find that the present matter fraction of the critical density is $Ω_{\rm m}=0.31^{+0.27}_{-0.14}$ (68%) $^{+0.12}_{-0.10}$ (systematic). For a flat universe with a constant equation of state for dark energy $w = p_x({pressure})/ρ_x({energy density})$, we find $w < -0.55^{+0.18}_{-0.11}$ (68%).

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K. -H. Chae, A. D. Biggs, R. D. Blandford, I. W. A. Browne, A. G. de Bruyn, C. D. Fassnacht, P. Helbig, N. J. Jackson, L. J. King, L. V. E. Koopmans, S. Mao, D. R. Marlow, J. P. McKean, S. T. Myers, M. Norbury, T. J. Pearson, P. M. Phillips, A. C. S. Readhead, D. Rusin, C. M. Sykes, P. N. Wilkinson, E. Xanthopoulos, T. York. 2002-09-28. Constraints on Cosmological Parameters from the Analysis of the Cosmic Lens All Sky Survey Radio-Selected Gravitational Lens Statistics. https://doi.org/10.1103/physrevlett.89.151301

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