Browsing by Author "Lohfink, A."

Now showing 1 - 3 of 3
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    BAT AGN Spectroscopic Survey - XII. The relation between coronal properties of active galactic nuclei and the Eddington ratio.
    (2018) Ricci, Claudio; Bauer, Franz Erik; Treister, Ezequiel; Ho, L. C.; Fabian, AC.; Trakhtenbrot, B.; Koss, M.; Ueda, Y.; Lohfink, A.; Shimizu, T.; Mushotzky, R.
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    The NuSTAR X-ray spectrum of the low-luminosity active galactic nucleus in NGC 7213
    (2015) Ursini, F.; Marinucci, A.; Matt, G.; Bianchi, S.; Tortosa, A.; Stern, D.; Arévalo, P.; Ballantyne, D.; Bauer, Franz Erik; Fabian, A.; Harrison, F.; Lohfink, A.; Reynolds, C.; Walton, D.
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    The soft-X-ray emission of Ark 120. XMM-Newton, NuSTAR, and the importance of taking the broad view
    (OXFORD UNIV PRESS, 2014) Matt, G.; Marinucci, A.; Guainazzi, M.; Brenneman, L. W.; Elvis, M.; Lohfink, A.; Arevalo, P.; Boggs, S. E.; Cappi, M.; Christensen, F. E.; Craig, W. W.; Fabian, A. C.; Fuerst, F.; Hailey, C. J.; Harrison, F. A.; Parker, M.; Reynolds, C. S.; Stern, D.; Walton, D. J.; Zhang, W. W.
    We 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.