X-ray observations of powerful AGN outflows - implications for feedback

Abstract

Highly ionised winds with velocities ~ 0.1-0.2c were first detected in X-ray spectra of non-BAL AGN a decade ago. Subsequent observations and archival searches have shown such winds to be a common feature of luminous AGN, increasing the belief that powerful ionised winds have a wider importance in galaxy feedback models. Paradoxically, for the best-quantified high velocity outflow (the luminous Seyfert PG1211+143) the wind appears too powerful to be compatible with the observed stellar bulge and black hole masses, suggesting the energy coupling of wind to bulge gas must be inefficient. A recent XMM-Newton observation of the narrow line Seyfert NGC 4051 offers an explanation of this apparent paradox, finding evidence for the fast ionised wind to lose most of its kinetic energy after shocking against the ISM. Importantly, the wind momentum is maintained through such a shock, supporting the view that a momentum-driven flow provides the critical link between black hole and stellar bulge masses implied by the observed M-sigma relationship.

14 pages, 7 figures To be published in Space Science Reviews and as hard cover in the Space Science Series of ISSI: The Physics of Accretion onto Black Holes (Springer Publisher)

References in corpus (8)

• The Suzaku view of highly-ionised outflows in AGN: I - Statistical detection and global absorber properties
• On why the Iron K-shell absorption in AGN is not a signature of the local Warm/Hot Intergalactic Medium
• Fe K Emission and Absorption in the XMM-EPIC Spectrum of the Seyfert Galaxy IC 4329a
• Confirming the high velocity outflow in PG 1211+143
• Relativistic blue- and red-shifted absorption lines in AGNs
• The shocked outflow in NGC 4051 - momentum-driven feedback, UFO's and warm absorbers
• On the evidence for narrow, relativistically shifted X-ray lines
• Is the X-ray spectrum of the narrow emission line QSO PG1211+143 defined by its energetic outflow?

Cited by in corpus (7)

• The variable, fast soft X-ray wind in PG 1211+143
• The XMM deep survey in the CDF-S. IX. An X-ray outflow in a luminous obscured quasar at z~1.6
• Detection of a second high velocity component in the highly ionized wind from PG 1211+143
• The Cepheid Distance to the Narrow-Line Seyfert 1 Galaxy NGC 4051
• Accretion disk winds in active galactic nuclei: X-ray observations, models, and feedback
• Exploring accretion disc physics and black hole growth with regular monitoring of ultrafast AGN winds
• Supermassive Black Hole Winds in X-rays: SUBWAYS IV. Tracing Radio Emission and Unveiling the Role of Winds