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X-Ray Spectral Variability of the Seyfert Galaxy NGC 4051 Observed with Suzaku
Y. Terashima, L. C. Gallo, H. Inoue +13
We report results from a Suzaku observation of the narrow-line Seyfert 1 NGC 4051. During our observation, large amplitude rapid variability is seen and the averaged 2--10 keV flux…
A longer XMM-Newton look at I Zwicky 1: Distinct modes of X-ray spectral variability
L. C. Gallo, W. N. Brandt, E. Costantini +1
The short-term spectral variability of the narrow-line Seyfert 1 galaxy I Zwicky 1 (I Zw 1) as observed in an 85 ks XMM-Newton observation is discussed in detail. I Zw 1 shows dist…
A longer XMM-Newton look at I Zwicky 1: Variability of the X-ray continuum, absorption, and iron Kalpha line
L. C. Gallo, W. N. Brandt, E. Costantini +3
We present the second XMM-Newton observation (85 ks) of the narrow-line Seyfert 1 galaxy (NLS1) I Zw 1 and describe its mean spectral and timing characteristics. On average, I Zw 1…
The spectral energy distribution of PKS 2004-447: a compact steep-spectrum source and possible radio-loud narrow-line Seyfert 1 galaxy
L. C. Gallo, P. G. Edwards, E. Ferrero +10
(abridged) The spectral energy distribution (SED) of the compact steep spectrum (CSS) source and possible radio-loud narrow-line Seyfert 1 galaxy (NLS1), PKS2004-447, is presented.…
Investigating the nature of narrow-line Seyfert 1 galaxies with high-energy spectral complexity
L. C. Gallo
(abridged) With the commissioning of XMM came the discovery of 2.5-10 keV spectral complexity in some narrow-line Seyfert 1 galaxies (NLS1). In this work, we define two samples of…
An explanation for the soft X-ray excess in AGN (Conference proceedings version)
J Crummy, AC Fabian, L Gallo +1
We present a large sample of type 1 AGN spectra taken with XMM-Newton. We fit them with the relativistically blurred photoionized disc model of Ross & Fabian (2005). This model is…