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arXiv · astro-ph/9706278

Weak lensing correlations in open and flat universes

J. L. Sanz·E. Martinez-Gonzalez·N. Benitez
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Abstract

Correlations between the magnification or polarization of background sources, induced by gravitational lensing due to the large-scale structure, and the positions of foreground galaxies are investigated. We found that their amplitude is enhanced with respect to correlations for a single population. We analize the dependence of the correlations with the density parameter Ωconsidering a nonlinear evolution of the matter power spectrum. The contribution of the linear evolution is negligible at scales below several arcminutes. Detailed results on the dependence of the correlations on the redshift of the foreground and background populations for different cosmological models are presented. The effect reaches its maximum amplitude for foreground populations with relatively small redshifts due to the fast increase of the nonlinear matter power spectrum at recent times.

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J. L. Sanz, E. Martinez-Gonzalez, N. Benitez. 1997-06-27. Weak lensing correlations in open and flat universes. https://doi.org/10.1093/mnras%2F291.3.418

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