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arXiv · astro-ph/9407004

Mapping the Dark Matter in Clusters

Nick Kaiser·Gordon Squires·Greg Fahlman·David Woods
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Abstract

Massive clusters of galaxies gravitationally shear the images of faint background galaxies. At large impact parameters the shear is weak, but can still be measured, to a reasonable degree of significance, as a statistical anisotropy of the faint galaxy images. We describe techniques for measuring the shear and discuss the interpretation of the shear field. We have applied this analysis to ms1224+007. We find a clear detection of the shear, but, puzzlingly, we find a mass about three times that obtained by application of the virial theorem, and obtain a very large mass-to-light ratio. Similar results have been obtained by other groups, and we discuss their implications.

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Nick Kaiser, Gordon Squires, Greg Fahlman, David Woods. 1994-07-01. Mapping the Dark Matter in Clusters. https://arxiv.org/abs/astro-ph/9407004

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