Magnified Views of the Ultrafast Outflow of the z = 1.51 Active Galactic Nucleus HS 0810+2554
Abstract
We present results from an observation of the gravitationally lensed z = 1.51 narrow absorption line (NAL) active galactic nucleus (AGN) HS 0810+2554 performed with the Chandra X-Ray Observatory. The factor of ~100 lensing magnification of HS 0810+2554 makes this source exceptionally bright. Absorption lines are detected at rest-frame energies of ~7.7 keV and ~11.0 keV at gsim97% significance. By interpreting these lines to arise from highly ionized iron the implied outflow velocities of the X-ray absorbing gas corresponding to these lines are 0.13c and 0.41c, respectively. The presence of these relativistic outflows and the absence of any significant low-energy X-ray absorption suggest that a shielding gas is not required for the generation of the relativistic X-ray absorbing winds in HS 0810+2554. UV spectroscopic observations with VLT/UVES indicate that the UV absorbing material is outflowing at v UV ~0.065c. Our analysis indicates that the fraction of the total bolometric energy released by HS 0810+2554 into the intergalactic medium (IGM) in the form of kinetic energy is epsilonk = 1.0_{-0.6}^{+0.8}. An efficiency of greater than unity implies that magnetic driving is likely a significant contributor to the acceleration of this X-ray absorbing wind. We also estimate the mass-outflow rate of the strongest absorption component to be \dot{M}_abs = 1.1_{-0.7}^{+0.9} M ⊙ yr-1. Assuming that the energetic outflow detected in the NAL AGN HS 0810+2554 is a common property of most AGN it would suggest that the X-ray absorbing wind may have a larger opening angle than previously thought. This has important consequences for estimating the feedback contribution of X-ray absorbing winds to the surrounding IGM.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 2014
- DOI:
- 10.1088/0004-637X/783/1/57
- arXiv:
- arXiv:1401.4486
- Bibcode:
- 2014ApJ...783...57C
- Keywords:
-
- galaxies: evolution;
- galaxies: formation;
- intergalactic medium;
- quasars: absorption lines;
- X-rays: galaxies;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 25 pages, includes 11 figures, Accepted for publication in ApJ