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arXiv · astro-ph/0310756

Properties of galaxy dark matter halos from weak lensing

Henk Hoekstra·Howard K. C. Yee·Michael D. Gladders
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Abstract

We present the results of a study of the average mass profile around galaxies using weak gravitational lensing. We use 45.5 deg^2 of R_C band imaging data from the Red-Sequence Cluster Survey (RCS) and define a sample of 1.2\times 10^5 lenses with 19.5 =0.20^{+0.04}_{-0.05}, in fair agreement with results from numerical simulations of CDM. Alternative theories of gravity (without dark matter) predict an isotropic lensing signal, which is excluded with 99.5% confidence. Hence, our results provide strong support for the existence of dark matter.

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Henk Hoekstra, Howard K. C. Yee, Michael D. Gladders. 2003-10-27. Properties of galaxy dark matter halos from weak lensing. https://arxiv.org/abs/astro-ph/0310756

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