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arXiv · 1411.2611

Probing the circumgalactic medium of active galactic nuclei with background quasars

Glenn G. Kacprzak·Christopher W. Churchill·Michael T. Murphy·Jeff Cooke
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Abstract

We performed a detailed study of the extended cool gas, traced by MgII absorption [$W_r(2796)\geq0.3$~Å], surrounding 14 narrow-line active galactic nuclei (AGNs) at 0.12 50$ km/s, indicating outflowing gas. The 2/2 intrinsic MgII systems have outflow velocities a factor of $\sim4$ higher than the NaID outflow velocities. Our results are consistent with AGN-driven outflows destroying the cool gas within their halos, which dramatically decreases their cool gas covering fraction, while star-burst driven winds are expelling cool gas into their circumgalactic media (CGM). This picture appears contrary to quasar--quasar pair studies which show that the quasar CGM contains significant amounts of cool gas whereas intrinsic gas found `down-the-barrel' of quasars reveals no cool gas. We discuss how these results are complementary and provide support for the AGN unified model.

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Glenn G. Kacprzak, Christopher W. Churchill, Michael T. Murphy, Jeff Cooke. 2014-11-10. Probing the circumgalactic medium of active galactic nuclei with background quasars. https://doi.org/10.1093/mnras%2Fstu2324

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