A Caltech Library Service

The rhythm of Fairall 9 - I: Observing the spectral variability with XMM-Newton and NuSTAR

Lohfink, A. M. and Reynolds, C. S. and Pinto, C. and Alston, W. and Boggs, S. E. and Christensen, F. E. and Craig, W. W. and Fabian, A. C. and Hailey, C. J. and Harrison, F. A. and Kara, E. and Matt, G. and Parker, M. L. and Stern, D. and Walton, D. and Zhang, W. W. (2016) The rhythm of Fairall 9 - I: Observing the spectral variability with XMM-Newton and NuSTAR. Astrophysical Journal, 821 (1). Art. No. 11. ISSN 0004-637X. doi:10.3847/0004-637X/821/1/11.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


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 spatially distinct Comptonizing region. Alternatively, a more complex primary Comptonization component together with blurred ionized reflection could be responsible.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Pinto, C.0000-0003-2532-7379
Alston, W.0000-0003-2658-6559
Boggs, S. E.0000-0001-9567-4224
Christensen, F. E.0000-0001-5679-1946
Fabian, A. C.0000-0002-9378-4072
Harrison, F. A.0000-0003-2992-8024
Kara, E.0000-0003-0172-0854
Matt, G.0000-0002-2152-0916
Parker, M. L.0000-0002-8466-7317
Stern, D.0000-0003-2686-9241
Walton, D.0000-0001-5819-3552
Zhang, W. W.0000-0002-1426-9698
Additional Information:© 2016 The American Astronomical Society. All rights reserved. Received 2015 July 5; accepted 2016 February 17; published 2016 April 4. We thank the referee for their comments that have helped to improve the clarity of the paper. AL and ACF acknowledge support from ERC Advanced Grant FEEDBACK. CSR thanks the Simons Foundation Fellows Program (US) and the Sackler Fellowship Program (Cambridge) for support. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTAR-DAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of data obtained from the Suzaku satellite, a collaborative mission between the space agencies of Japan (JAXA) and the USA (NASA).
Group:NuSTAR, Space Radiation Laboratory
Funding AgencyGrant Number
European Research Council (ERC)FEEDBACK
Simons FoundationUNSPECIFIED
Sackler Fellowship Program (Cambridge)UNSPECIFIED
Subject Keywords:galaxies: individual(Fairall 9) – X-rays: galaxies – galaxies: nuclei – galaxies: Seyfert –black hole physics
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory2016-03
Issue or Number:1
Record Number:CaltechAUTHORS:20160318-105917798
Persistent URL:
Official Citation:A. M. Lohfink et al 2016 ApJ 821 11
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:65482
Deposited By: Ruth Sustaita
Deposited On:18 Mar 2016 19:04
Last Modified:10 Nov 2021 23:46

Repository Staff Only: item control page