Skip to content
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Publication Details
AFRICAN RESEARCH NEXUS
SHINING A SPOTLIGHT ON AFRICAN RESEARCH
general
Active galactic nuclei as scaled-up Galactic black holes
Nature, Volume 444, No. 7120, Year 2006
Notification
URL copied to clipboard!
Description
A long-standing question is whether active galactic nuclei (AGN) vary like Galactic black hole systems when appropriately scaled up by mass. If so, we can then determine how AGN should behave on cosmological timescales by studying the brighter and much faster varying Galactic systems. As X-ray emission is produced very close to the black holes, it provides one of the best diagnostics of their behaviour. A characteristic timescale - which potentially could tell us about the mass of the black hole - is found in the X-ray variations from both AGN and Galactic black holes, but whether it is physically meaningful to compare the two has been questioned. Here we report that, after correcting for variations in the accretion rate, the timescales can be physically linked, revealing that the accretion process is exactly the same for small and large black holes. Strong support for this linkage comes, perhaps surprisingly, from the permitted optical emission lines in AGN whose widths (in both broad-line AGN and narrow-emission-line Seyfert 1 galaxies) correlate strongly with the characteristic X-ray timescale, exactly as expected from the AGN black hole masses and accretion rates. So AGN really are just scaled-up Galactic black holes. ©2006 Nature Publishing Group.
Authors & Co-Authors
McHardy, Ian M.M.
United Kingdom, Southampton
University of Southampton
K̈ording, Elmar G.
United Kingdom, Southampton
University of Southampton
Knigge, Christian
United Kingdom, Southampton
University of Southampton
Uttley, Philip
Netherlands, Amsterdam
Universiteit Van Amsterdam
Fender, Robert P.
United Kingdom, Southampton
University of Southampton
Statistics
Citations: 517
Authors: 5
Affiliations: 2
Identifiers
Doi:
10.1038/nature05389
ISSN:
00280836
Research Areas
Environmental