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Galaxy evolution. Black hole feedback in the luminous quasar PDS 456
E Nardini1, J N Reeves2, J Gofford2
1Astrophysics Group, School of Physical and Geographical Sciences, Keele University, Keele, Staffordshire ST5 5BG, UK. e.nardini@keele.ac.uk.
Science (New York, N.Y.)
|February 21, 2015
Summary
We detected a persistent, relativistic outflow of ionized gas from the quasar PDS 456. This powerful wind suggests a mechanism for supermassive black hole and galaxy coevolution.
Area of Science:
- Astrophysics
- Cosmic Evolution
- Black Hole Physics
Background:
- Galaxy evolution is intrinsically linked to the growth of supermassive black holes (SMBHs).
- During quasar phases, SMBHs release immense energy, influencing their host galaxies via radiation-driven winds.
Purpose of the Study:
- To investigate the physical processes driving the coevolution of SMBHs and their host galaxies.
- To detect and characterize outflows from luminous quasars.
Main Methods:
- Analysis of broadband X-ray spectra from the luminous quasar PDS 456 over five distinct epochs.
- Identification of spectral signatures indicative of highly ionized gas outflows.
Main Results:
- Detection of a persistent, nearly spherical outflow of highly ionized gas.
- The outflow is expelled at relativistic speeds from the accretion disk.
- The outflow's kinetic power exceeds 10(46) ergs per second, indicating significant feedback potential.
Conclusions:
- The observed outflow provides strong evidence for effective feedback mechanisms in quasars.
- This finding supports models of SMBH and host galaxy coevolution.
- The wide aperture of the outflow suggests efficient coupling with the ambient galactic environment.
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