THE RHYTHM OF FAIRALL 9. I. OBSERVING THE SPECTRAL VARIABILITY WITH XMM-NEWTON AND NuSTAR

Journal Article · Sun Apr 10 00:00:00 EDT 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/821/1/11· OSTI ID:22518514

Lohfink, A. M.; Pinto, C.; Alston, W.; Fabian, A. C.; Kara, E.; Parker, M. L. ^[1]; Reynolds, C. S. ^[2]; Boggs, S. E.; Craig, W. W. ^[3]; Christensen, F. E.; Hailey, C. J. ^[4]; Harrison, F. A. ^[5]; Matt, G. ^[6]; Stern, D.; Walton, D. ^[7]

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1. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)
2. Department of Astronomy, University of Maryland College Park, College Park, Maryland 20742 (United States)
3. Space Sciences Laboratory, University of California, Berkeley, 7 Gauss Way, Berkeley, CA 94720-7450 (United States)
4. Danish Technical University, DK-2800 Lyngby (Denmark)
5. Cahill Center for Astronomy and Astrophysics, Caltech, Pasadena, CA 91125 (United States)
6. Dipartimento di Matematica e Fisica, Università degli Studi Roma Tre, via della Vasca Navale 84, I-00146 Roma (Italy)
7. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

We present a multi-epoch X-ray spectral analysis of the Seyfert 1 galaxy Fairall 9. Our analysis shows that Fairall 9 displays unique spectral variability in that its ratio residuals to a simple absorbed power law in the 0.5–10 keV band remain constant with time in spite of large variations in flux. This behavior implies an unchanging source geometry and the same emission processes continuously at work at the timescale probed. With the constraints from NuSTAR on the broad-band spectral shape, it is clear that the soft excess in this source is a superposition of two different processes, one being blurred ionized reflection in the innermost parts of the accretion disk, and the other a continuum component such as a spatially distinct Comptonizing region. Alternatively, a more complex primary Comptonization component together with blurred ionized reflection could be responsible.

• OSTI ID: 22518514
• Journal Information: Astrophysical Journal, Vol. 821, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCRETION DISKS
COSMIC X-RAY SOURCES
EMISSION SPECTRA
KEV RANGE
LIMITING VALUES
PROBES
REFLECTION
SEYFERT GALAXIES
VARIATIONS