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arXiv · 0711.2839

Radio loud AGN and the L_X - σrelation of galaxy groups and clusters

Shiyin Shen·Guinevere Kauffmann·Anja von der Linden·Simon D. M. White·P. N. Best
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Abstract

We use the ROSAT All-Sky Survey to study the X-ray properties of a sample of 625 groups and clusters of galaxies selected from the Sloan Digital Sky Survey. We stack clusters with similar velocity dispersions and investigate whether their average X-ray luminosities and surface brightness profiles vary with the radio activity level of their central galaxies. We find that at a given value of $σ$, clusters with a central radio AGN have more concentrated X-ray surface brightness profiles, larger central galaxy masses, and higher X-ray luminosities than clusters with radio-quiet central galaxies. The enhancement in X-ray luminosity is more than a factor of two, is detected with better than 6$σ$ significance, and cannot be explained by X-ray emission from the radio AGN itself. This difference is largely due to a subpopulation of radio-quiet, high velocity dispersion clusters with low mass central galaxies. These clusters are underluminous at X-ray wavelengths when compared to otherwise similar clusters where the central galaxy is radio-loud, more massive, or both.

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Shiyin Shen, Guinevere Kauffmann, Anja von der Linden, Simon D. M. White, P. N. Best. 2008-06-23. Radio loud AGN and the L_X - σrelation of galaxy groups and clusters. https://doi.org/10.1111/j.1365-2966.2008.13647.x

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