Twenty-Two Emission-Line AGNs From the HEAO-1 X-Ray Survey
Abstract
We report 22 emission-line active galactic nuclei as bright, hard x-ray sources. All of them appear to be new classifications with the exception of one peculiar IRAS source which is a known quasar and has no published spectrum. The objects were located on the basis of positional data from the HEAO-1 scanning modulation collimator and the HEAO-1 Large Area Sky Survey. A few of these AGN had been detected by the Uhuru and Ariel V surveys, and four are also IRAS sources. This sample exhibits a rich diversity in optical spectral properties and luminosities, ranging from a powerful broad-absorption-line quasar to a weak nucleus embedded in a nearby NGC galaxy. Two cases confer x-ray luminosities in excess of 10^47^ erg/s. However, there is a degree of uncertainty in the x-ray identification for the AGN fainter than V ~ 16.5. Optically, several AGNs exhibit very strong Fe II emission, continuing this tendency among the x- ray selected objects from HEAO-1. One seyfert galaxy with substantial radio flux is an exception to the common association of strong Fe II emission and radio-quiet AGN. The previously recognized IRAS quasar shows extreme velocities in the profiles of the forbidden lines; the O III pair is broadened to the point that the lines are blended (FWHM ~3500 km s^-1^). Several of these AGN show evidence of intrinsic obscuration, illustrating the effectiveness of hard x-ray surveys in locating AGN through high column density.
- Publication:
-
The Astronomical Journal
- Pub Date:
- June 1993
- DOI:
- 10.1086/116585
- Bibcode:
- 1993AJ....105.2079R
- Keywords:
-
- Active Galactic Nuclei;
- Emission Spectra;
- Heao 1;
- X Ray Sources;
- Quasars;
- Seyfert Galaxies;
- Sky Surveys (Astronomy);
- Astronomy;
- X-RAYS: GALAXIES;
- GALAXIES: ACTIVE