Possible Evidence for a Truncated Thin Disk in Seyfert 1 Galaxy NGC 4593
Abstract
We compile the multiband spectral energy distribution of Seyfert 1 galaxy NGC 4593 and investigate its optical-to-ultraviolet (OUV) continuum and iron Kα line profile. No strong ``big blue bump'' is found in the OUV band. The iron Kα line profile is not as broad as expected from a disk that extends down to the last stable orbit. Both of them can be modeled by a truncated thin disk, and they support the existence of a truncated thin disk in the system. It is of much interest that NGC 4593 may be a typical object with an accretion rate m=M/MEdd~0.01-0.1 and harbors a two-component accretion flow: an outer thin disk and an inner hot flow-possibly an advection-dominated accretion flow, analogous to the low and intermediate state of low-mass X-ray binaries.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2000
- DOI:
- 10.1086/312768
- arXiv:
- arXiv:astro-ph/0006004
- Bibcode:
- 2000ApJ...537L.103L
- Keywords:
-
- Accretion;
- Accretion Disks;
- Galaxies: General;
- Galaxies: Individual: NGC Number: NGC 4593;
- Galaxies: Active;
- Galaxies: Seyfert;
- Astrophysics
- E-Print:
- 5 pages, including 3 figures, accepted for publication in ApJL