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The LX-sigma Relation for Galaxies and Clusters of Galaxies

Andisheh Mahdavi·Margaret J. Geller
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Abstract

We demonstrate that individual elliptical galaxies and clusters of galaxies form a continuous X-ray luminosity---velocity dispersion (LX-sigma) relation. Our samples of 280 clusters and 57 galaxies have LX ~ sigma^4.4 and LX ~ sigma^10, respectively. This unified LX - sigma relation spans 8 orders of magnitude in LX and is fully consistent with the observed and theoretical luminosity---temperature scaling laws. Our results support the notion that galaxies and clusters of galaxies are the luminous tracers of similar dark matter halos.

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Andisheh Mahdavi, Margaret J. Geller. 2001-05-18. The LX-sigma Relation for Galaxies and Clusters of Galaxies. https://doi.org/10.1086/321710

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