Journal article · Preprint article
The soft-X-ray emission of Ark 120. XMM-Newton, NuSTAR, and the importance of taking the broad view
Università Roma Tre1
Technical University of Denmark2
Institute of Astronomy3
California Institute of Technology4
Columbia University5
NASA Jet Propulsion Laboratory6
NASA Goddard Space Flight Center7
European Space Astronomy Centre8
Harvard-Smithsonian Center for Astrophysics9
University of Maryland, College Park10
Pontifícia Universidade Católica11
University of California at San Diego12
National Institute for Astrophysics13
National Space Institute, Technical University of Denmark14
Astrophysics, National Space Institute, Technical University of Denmark15
...and 5 moreWe present simultaneous XMM-Newton and NuSTAR observations of the 'bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard-X-ray spectral coverage allows us to constrain different models for the excess soft-X-ray emission. Among phenomenological models, a cutoff power law best explains the soft-X-ray emission.
This model likely corresponds to Comptonization of the accretion disc seed UV photons by a population of warm electrons: using Comptonization models, a temperature of similar to 0.3 keV and an optical depth of similar to 13 are found. If the UV-to-X-ray optxagnf model is applied, the UV fluxes from the XMM-Newton Optical Monitor suggest an intermediate black hole spin.
Contrary to several other sources observed by NuSTAR, no high-energy cutoff is detected with a lower limit of 190 keV.
| Language: | English |
|---|---|
| Publisher: | Royal Astronomical Society |
| Year: | 2014 |
| Pages: | 3016-3021 |
| ISSN: | 13652966 and 00358711 |
| Types: | Journal article and Preprint article |
| DOI: | 10.1093/mnras/stu159 |
| ORCIDs: | Christensen, Finn Erland |
