IDENTIFICATIONS OF FIVE INTEGRAL SOURCES VIA OPTICAL SPECTROSCOPY

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Butler S. C., Tomsick J. A., Chaty S., Heras J. A. Z., Rodriguez J., Walter R., ...More

ASTROPHYSICAL JOURNAL, vol.698, no.1, pp.502-508, 2009 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 698 Issue: 1
  • Publication Date: 2009
  • Doi Number: 10.1088/0004-637x/698/1/502
  • Journal Name: ASTROPHYSICAL JOURNAL
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.502-508
  • 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), X-RAY SOURCES, CHANDRA LOCALIZATIONS, GALACTIC PLANE, XMM-NEWTON, SPECTRA, VARIABILITY, LUMINOSITY, EMISSION, CATALOG, SYSTEM
  • Middle East Technical University Affiliated: Yes

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 (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.