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Cited by 676

The DOI matches its Crossref record; 11 of the 11 references it cites were found in a registry or an index.

Active galactic nuclei as scaled-up Galactic black holes

Open access
McHardy, I. M., Koerding, E., Knigge, C., Uttley, P., Fender, R. P.·2006·Nature

Abstract

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.

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Metadata

Authors
McHardy, I. M., Koerding, E., Knigge, C., Uttley, P., & Fender, R. P.
Venue
Nature
Published
2006-12
Volume
444
Issue
7120
Pages
730-732
ISSN
  • 0028-0836 (ISSN-L)
  • 1476-4687
OpenAlex
W1985523694
Cited by
676
References
11
FWCI
19.09
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: Active galactic nuclei as scaled-up Galactic black holes. https://app.cochat.ai/papers/10.1038/nature05389
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McHardy, I. M., Koerding, E., Knigge, C., Uttley, P., & Fender, R. P. (2006). Active galactic nuclei as scaled-up Galactic black holes. Nature. https://doi.org/10.1038/nature05389

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