2009/03/06 by Suzanne C. Butler, John A. Tomsick, Sylvain Chaty +10 · 32 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Galaxy #Gamma-ray bursts and supernovae #Physics #Pulsars and Gravitational Waves Research #Redshift #Spectroscopy #astro-ph.HE
paper · pdf · doi:10.1088/0004-637x/698/1/502
published in The Astrophysical Journal 698(1), 502-508 (IOP Publishing) · 8 pages, 5 figures, accepted for publication by ApJ
arxiv created 2009/03/06 · openalex publication_date 2009/05/21 · arxiv updated 2011/02/11 · openalex created_date 2019/06/27 · openalex updated_date 2026/08/05
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 (similar to 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 L0.3-10 (keV) = 5 x 10(36) erg s(-1) for IGR J18214-1318, L0.3-10 keV = 1.3 x 10(32) erg s(-1) for IGR J18308-1232, and L0.3-10 keV = 6.7 x 10(32) erg s(-1) for IGR J19267+1325.