A Chandra view of Naked Active Galactic Nuclei
arXiv:astro-ph/0703269 · doi:10.1086/518024
Abstract
We present the first X-ray observations of three sources belonging to a new AGN class: the naked AGNs. Based on optical spectroscopic studies, these sources appear as classical type 2 (obscured) AGNs, with only narrow emission lines. However, long-term optical monitoring campaigns, carried out over more than two decades, show that the same sources are strongly variable, like type 1 (un-obscured) AGNs. Based on short Chandra observations, the sources appear to be fairly bright in the X-rays, with typical Seyfert 1s values for the photon index (Gamma~1.8) and without significant intrinsic absorption, supporting the conclusion that some bright AGNs may genuinely lack a broad line region. Future, broad-band studies as well as deeper X-ray observations, probing both the spectral and the temporal properties of the naked AGNs, are crucial to shed light on the central engine of these sources, which may be representative of a large class of AGNs.
7 pages, 3 figures, accepted for publication in ApJ
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- Indecent Exposure in Seyfert 2 Galaxies: A Close Look
- Simultaneous X-ray and optical observations of true Type 2 Seyfert galaxies
- NGC3147: a "true" Seyfert 2 without the broad-line region
- Unabsorbed Seyfert 2 galaxies: the case of "naked" AGN
- Application of the Disk Evaporation Model to AGNs
- Optically-Selected BLR-less Active Galactic Nuclei from the SDSS Stripe82 Database I: The Sample
- Emission and Absorption Properties of Low-Mass Type 2 Active Galaxies with XMM-Newton
- Q2122-444: a naked AGN fully dressed
- XMM Observations of the Seyfert 2 Galaxy NGC 7590: the Nature of X-ray Absorption
- The X-ray Nature of Nucleus in Seyfert 2 Galaxy NGC 7590