|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'500'096
Articles rated: 2609
19 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
The Nature of Flat-Spectrum Nuclear Radio Emission in Seyfert Galaxies | | C.G. Mundell
; A.S. Wilson
; J.S. Ulvestad A.L. Roy
; | | Date: |
11 Dec 2000 | | Subject: | astro-ph | | Affiliation: | ARI, Liverpool John Moores University), A.S. Wilson (University of Maryland), J.S. Ulvestad(NRAO, Socorro) A.L. Roy (MPIfRA, Bonn | | Abstract: | Parsec-scale VLBA imaging of five Seyfert galaxies with flat-spectrum radio nuclei was conducted to determine whether the flat spectrum represents thermal emission from the accretion disk/obscuring torus or nonthermal, synchrotron self-absorbed emission. Four of the five show emission consistent with synchrotron self-absorption, with intrinsic sizes ~0.05-0.2 pc (or 10^4 gravitational radii for a 10^8 Msun black hole for the smallest). In contrast, NGC 4388, which was detected with MERLIN but not the VLBA, shows thermal emission with similar properties to that detected in NGC 1068. It is notable that the two Seyfert galaxies with detected thermal nuclear radio emission both have large X-ray absorbing columns, suggesting that columns in excess of ~10^{24} cm^{-2} are needed for such disks to be detectable. | | Source: | arXiv, astro-ph/0012228 | | 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 claudebot
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER