|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'501'711
Articles rated: 2609
20 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
X-ray Variability as a Probe of Advection-Dominated Accretion in Low-Luminosity AGN | | A. Ptak
; T. Yaqoob
; R. Mushotzky
; P. Serlemitsos
; R. Griffiths
; | | Date: |
29 Apr 1998 | | Subject: | astro-ph | | Abstract: | As a class, LINERs and Low-Luminosity AGN tend to show little or no significant short-term variability (i.e., with time-scales less than a day). This is a marked break for the trend of increased variability in Seyfert 1 galaxies with decreased luminosity. We propose that this difference is due to the lower accretion rate in LINERs and LLAGN which is probably causing the accretion flow to be advection-dominated. This results in a larger characteristic size for the X-ray producing region than is the case in ``normal’’ AGN. Short-term variability may be caused by a localized instability or occultation events, but we note that such events would likely be accompanied by broad-band spectral changes. Since the ADAF is more compact in a Kerr metric, it is possible that the X-ray emission from ADAFs around rotating blackholes would be more variable than X-ray emission from ADAFs in a Schwarzchild metric. Similar variability arguments also apply to other wavelengths, and accordingly multiwavelength monitoring of LLAGN could serve to ``map’’ the ADAF regions. | | Source: | arXiv, astro-ph/9804327 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER