Identifications of Five INTEGRAL Sources via Optical Spectroscopy
Abstract
The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) is discovering hundreds of new hard X-ray sources, many of which remain unidentified. We report on optical spectroscopy of five such sources for which X-ray observations at lower energies (~0.5-10 keV) and higher angular resolutions than INTEGRAL have allowed for unique optical counterparts to be located. We find that INTEGRAL Gamma-Ray (IGR) J16426+6536 and IGR J22292+6647 are Type 1 Seyfert active galactic nuclei (with IGR J16426+6536 further classified as a Seyfert 1.5) which have redshifts of z = 0.323 and z = 0.113, respectively. IGR J18308-1232 is identified as a cataclysmic variable (CV), and we confirm a previous identification of IGR J19267+1325 as a magnetic CV. IGR J18214-1318 is identified as an obscured high-mass X-ray binary (HMXB), which are systems thought to have a compact object embedded in the stellar wind of a massive star. We combine Chandra fluxes with distances based on the optical observations to calculate X-ray luminosities of the HMXB and CVs, finding L 0.3-10 keV = 5 × 1036 erg s-1 for IGR J18214-1318, L 0.3-10 keV = 1.3 × 1032 erg s-1 for IGR J18308-1232, and L 0.3-10 keV = 6.7 × 1032 erg s-1 for IGR J19267+1325.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 2009
- DOI:
- 10.1088/0004-637X/698/1/502
- arXiv:
- arXiv:0903.1302
- Bibcode:
- 2009ApJ...698..502B
- Keywords:
-
- galaxies: Seyfert;
- novae;
- cataclysmic variables;
- techniques: spectroscopic;
- X-rays: binaries;
- X-rays: individual: IGR J16426+6536 IGR J18214–1318 IGR J18308–1232 IGR J19267+1325 IGR J22292+6647;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 8 pages, 5 figures, accepted for publication by ApJ