%0 Generic %1 kacprzak2014probing %A Kacprzak, Glenn G. %A Churchill, Christopher W. %A Murphy, Michael T. %A Cooke, Jeff %D 2014 %K agn cgm galaxy gas low-z %T Probing the circumgalactic medium of active galactic nuclei with background quasars %U http://arxiv.org/abs/1411.2611 %X We performed a detailed study of the extended cool gas, traced by MgII absorption $W_r(2796)\geq0.3$~\AA, surrounding 14 narrow-line active galactic nuclei (AGNs) at 0.12<z<0.22 using background quasar sight-lines. The background quasars probe the AGNs at projected distances of $60łeq Dłeq265$~kpc. We find that, between $100Dłeq200$~kpc, AGNs appear to have lower MgII gas covering fractions (0.09$^+0.18_-0.08$) than quasars (0.47$^+0.16_-0.15$) and possibly lower than in active field galaxies (0.25$^+0.11_-0.09$). We do not find a statistically significant azimuthal angle dependence for the MgII covering fraction around AGNs, though the data hint at one. We also study the `down-the-barrel' outflow properties of the AGNs themselves and detect intrinsic NaID absorption in 8/8 systems and intrinsic MgII absorption in 2/2 systems, demonstrating that the AGNs have significant reservoirs of cool gas. We find that 6/8 NaID and 2/2 MgII intrinsic systems contain blueshifted absorption with $\Delta v>50$ 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.

@misc{kacprzak2014probing, abstract = {We performed a detailed study of the extended cool gas, traced by MgII absorption [$W_r(2796)\geq0.3$~{\AA}], surrounding 14 narrow-line active galactic nuclei (AGNs) at 0.12<z<0.22 using background quasar sight-lines. The background quasars probe the AGNs at projected distances of $60\leq D\leq265$~kpc. We find that, between $100\leq D\leq200$~kpc, AGNs appear to have lower MgII gas covering fractions (0.09$^{+0.18}_{-0.08}$) than quasars (0.47$^{+0.16}_{-0.15}$) and possibly lower than in active field galaxies (0.25$^{+0.11}_{-0.09}$). We do not find a statistically significant azimuthal angle dependence for the MgII covering fraction around AGNs, though the data hint at one. We also study the `down-the-barrel' outflow properties of the AGNs themselves and detect intrinsic NaID absorption in 8/8 systems and intrinsic MgII absorption in 2/2 systems, demonstrating that the AGNs have significant reservoirs of cool gas. We find that 6/8 NaID and 2/2 MgII intrinsic systems contain blueshifted absorption with $\Delta v>50$ 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.}, added-at = {2014-11-12T09:58:45.000+0100}, author = {Kacprzak, Glenn G. and Churchill, Christopher W. and Murphy, Michael T. and Cooke, Jeff}, biburl = {https://www.bibsonomy.org/bibtex/25985224e6995509ab3e76caeb7418617/miki}, description = {[1411.2611] Probing the circumgalactic medium of active galactic nuclei with background quasars}, interhash = {ac5f6cd629ac1ae48e89f5125d1733c7}, intrahash = {5985224e6995509ab3e76caeb7418617}, keywords = {agn cgm galaxy gas low-z}, note = {cite arxiv:1411.2611Comment: 10 pages, 6 figures, accepted 01/11/2014 for publication in MNRAS}, timestamp = {2014-11-12T09:58:45.000+0100}, title = {Probing the circumgalactic medium of active galactic nuclei with background quasars}, url = {http://arxiv.org/abs/1411.2611}, year = 2014 }