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arXiv · astro-ph/0110093

Strong Gravitational Lensing and Dark Energy

Nick Sarbu·David Rusin·Chung-Pei Ma
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Abstract

We investigate the statistics of gravitational lenses in flat, low-density cosmological models with different cosmic equations of state w. We compute the lensing probabilities as a function of image separation θusing a lens population described by the mass function of Jenkins et al. and modeled as singular isothermal spheres on galactic scales and as Navarro, Frenk & White halos on cluster scales. It is found that COBE-normalized models with w > - 0.4 produce too few arcsecond-scale lenses in comparison with the JVAS/CLASS radio survey, a result that is consistent with other observational constraints on w. The wide-separation (θ> 4'') lensing rate is a particularly sensitive probe of both w and the halo mass concentration. The absence of these systems in the current JVAS/CLASS data excludes highly concentrated halos in w < -0.7 models. The constraints can be improved by ongoing and future lensing surveys of > 10^5 sources.

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Nick Sarbu, David Rusin, Chung-Pei Ma. 2001-10-04. Strong Gravitational Lensing and Dark Energy. https://doi.org/10.1086/324679

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