Multiple-images in the cluster lens Abell 2218: Constraining the geometry of the Universe?
- Creators
- Soucail, G.
- Kneib, J.-P.
- Golse, G.
Abstract
In this Letter we present a detailed study of the lensing configuration in the cluster Abell 2218. Four multiple-images systems with measured spectroscopic redshifts have been identified in this cluster. These multiple images are very useful to constrain accurately the mass distribution in the cluster core, but they are also sensitive to the value of the geometrical cosmological parameters of the Universe. Using a simplified maximum likelihood analysis we find 0 < Ω_M < 0.30 assuming a flat Universe, and 0 < Ω_M < 0.33 and w < -0.85 for a flat Universe with dark energy. Interestingly, an Einstein-de Sitter model is excluded at more than 4σ. These constraints are consistent with the current constraints derived with CMB anisotropies or supernovae studies. The proposed method constitutes an independent test of the geometrical cosmological parameters of the Universe and we discuss the limits of this method and this particular application to Abell 2218. Application of this method with more sophisticated tools and to a larger number of clusters or with more multiple images constraints, will put stringent constraints on the geometrical cosmological parameters.
Additional Information
© 2004 ESO. Article published by EDP Sciences. Received 23 October 2003; Accepted 25 February 2004; Published online 26 March 2004. We wish to thank B. Fort, R. Pain, M. Douspis and R. Blandford for encouragements and fruitful discussions. Part of this work was supported by the European Network LENSNET: "Gravitational Lensing: New Constraints on Cosmology and the Distribution of Dark Matter'' of the European Commission under contract No: ERBFMRX-CT98-0172 and by the Programme National de Cosmologie of the CNRS. JPK acknowledges support from CNRS and Caltech. JPK and GS thank W.M. Keck Observatory and CFHT respectively, for their hospitality.Attached Files
Published - aafj233.pdf
Accepted Version - 0402658.pdf
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Additional details
- Eprint ID
- 84986
- Resolver ID
- CaltechAUTHORS:20180228-081549033
- ERBFMRX-CT98-0172
- European Commission
- Centre National de la Recherche Scientifique (CNRS)
- Caltech
- Programme National Galaxies et Cosmologie (PNCG)
- Created
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2018-02-28Created from EPrint's datestamp field
- Updated
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2021-11-15Created from EPrint's last_modified field