NuSTAR reveals extreme absorption in z < 0.5 TYPE 2 quasars

Journal Article · Thu Aug 20 04:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/809/2/115· OSTI ID:22882778

Lansbury, G. B.; Gandhi, P.; Alexander, D. M.; Annuar, A.; Del Moro, A. ^[1]; Assef, R. J. ^[2]; Aird, J. ^[3]; Ballantyne, D. R. ^[4]; Baloković, M.; Brightman, M.; Grefenstette, B. W.; Harrison, F. A. ^[5]; Bauer, F. E. ^[6]; Boggs, S. E. ^[7]; Brandt, W. N. ^[8]; Christensen, F. E.; Craig, W. W. ^[9]; Civano, F. ^[10]; Comastri, A. ^[11]; others, and

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1. Centre for Extragalactic Astronomy, Department of Physics, University of Durham, South Road, Durham DH1 3LE (United Kingdom)
2. Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile)
3. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA (United Kingdom)
4. Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States)
5. Cahill Center for Astrophysics, 1216 East California Boulevard, California Institute of Technology, Pasadena, CA 91125 (United States)
6. Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, 306, Santiago 22 (Chile)
7. Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States)
8. Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States)
9. DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark)
10. Yale Center for Astronomy and Astrophysics, Physics Department, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States)
11. INAF Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy)

The intrinsic column density (N{sub H}) distribution of quasars is poorly known. At the high obscuration end of the quasar population and for redshifts z < 1, the X-ray spectra can only be reliably characterized using broad-band measurements that extend to energies above 10 keV. Using the hard X-ray observatory NuSTAR, along with archival Chandra and XMM-Newton data, we study the broad-band X-ray spectra of nine optically selected (from the SDSS), candidate Compton-thick (N{sub H} > 1.5 × 10{sup 24} cm{sup −2}) type 2 quasars (CTQSO2s); five new NuSTAR observations are reported herein, and four have been previously published. The candidate CTQSO2s lie at z < 0.5, have observed [O iii] luminosities in the range 8.4

• OSTI ID: 22882778
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 809; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United Kingdom
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABSORPTION
COMPUTERIZED SIMULATION
DENSITY
DISTRIBUTION
GALAXY NUCLEI
HARD X RADIATION
KEV RANGE 10-100
LUMINOSITY
QUASARS
RED SHIFT
X-RAY GALAXIES
X-RAY SPECTRA