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Large scatter in X-ray emission among elliptical galaxies: correlations with mass of host halo

W. G. Mathews·F. Brighenti·A. Faltenbacher·D. A. Buote·P. J. Humphrey·F. Gastaldello·L. Zappacosta
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Abstract

The enormous range of X-ray luminosities among elliptical galaxies with similar optical luminosities can be attributed to large scatter and systematic variations in the dark halo mass determined from X-ray observations. The mean halo mass decreases sharply with both the X-ray and K-band luminosities. Smaller halos contain less diffuse hot gas and have lower X-ray luminosities. In addition the hot gas in low mass halos is more easily depleted by supernova-driven outflows, further lowering the X-ray luminosity.

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W. G. Mathews, F. Brighenti, A. Faltenbacher, D. A. Buote, P. J. Humphrey, F. Gastaldello, L. Zappacosta. 2006-10-24. Large scatter in X-ray emission among elliptical galaxies: correlations with mass of host halo. https://doi.org/10.1086/509915

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