News on Dark Matter in Galaxies and Clusters

F. Combes; D. Pfenniger

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arXiv · astro-ph/9407013

News on Dark Matter in Galaxies and Clusters

F. Combes·D. Pfenniger

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Abstract

Major progresses have been made this last year towards a better knowledge of the invisible mass. Michel Spiro will talk in details about the micro-lensing experiments and their promising results; the ROSAT satellite has provided extended X-ray maps of the hot gas, which traces dark matter in galaxy clusters: they reveal lower amounts of dark matter in clusters than was previously derived; the dark to visible mass in clusters is not larger than its value in spiral galaxies. It was shown, by X-ray data and gravitational lenses analysis that the dark matter density is highly peaked towards the cluster centers. A new dark matter candidate has also been proposed, in the form of cold and fractal molecular gas that could be present around most late-type spiral galaxies and account for the observed flat rotation curves.

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F. Combes, D. Pfenniger. 1994-07-05. News on Dark Matter in Galaxies and Clusters. https://arxiv.org/abs/astro-ph/9407013

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