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A ROSAT Search for X-ray Emission from Quasar Host Clusters

Patrick B. Hall·Erica Ellingson·Richard F. Green·Howard Yee
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Abstract

We report the results of a search for X-ray emission from quasar host clusters at moderate redshift using the {\sl ROSAT} HRI. We detect no emission from the host clusters of 3C~263 (z=0.646) and PKS~2352-34 (z=0.706) to 3$σ$\ limits of 3.26 and 2.86 $\times$10$^{44}$\ ergs~s$^{-1}$ respectively (H$_o$=50, q$_o$=1/2) for clusters with r$_{core}$=125~kpc and T=5~keV. These limits show that these quasar host clusters are not substantially more X-ray luminous than optically or X-ray selected clusters of similar richnesses at z$\gtrsim$0.5. We also report the possible detection of a clump of X-ray emitting gas coincident with the brightest radio lobe of 3C~263. This may be evidence for the existence of a clumpy ICM in the host cluster of 3C~263.

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Patrick B. Hall, Erica Ellingson, Richard F. Green, Howard Yee. 1995-06-05. A ROSAT Search for X-ray Emission from Quasar Host Clusters. https://doi.org/10.1086/117538

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