References of "Fabian, A. C"
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See detailBlack hole spin and size of the X-ray-emitting region(s) in the Seyfert 1.5 galaxy ESO 362-G18
Agis-Gonzalez, Beatriz ULiege; Miniutti, G.; Kara, E. et al

in Monthly Notices of the Royal Astronomical Society (2014), 443

We report results from multi-epoch X-ray observations of the Seyfert 1.5 galaxy ESO 362-G18 performed between 2005 November and 2010 June. ESO 362-G18 generally exhibits the typical X-ray spectrum of type ... [more ▼]

We report results from multi-epoch X-ray observations of the Seyfert 1.5 galaxy ESO 362-G18 performed between 2005 November and 2010 June. ESO 362-G18 generally exhibits the typical X-ray spectrum of type 1 active galactic nuclei. A disc-reflection component accounts for broad residuals in the iron K band and above 10 keV, as well as for a significant soft excess. From our best-fitting reflection model, we measure a black hole spin a ≥ 0.92 at the 99.99 per cent confidence level. ESO 362-G18 is also (typically) mildly absorbed by a column of neutral gas. The absorber is variable and one observation, performed ˜2 months after a typical mildly absorbed one, is heavily absorbed by a cold column density of ˜ 3-4 × 10[SUP]23[/SUP] cm[SUP]-2[/SUP], nearly two orders of magnitude higher than that during any other observation. UV variability between the heavily absorbed observation and the others suggests that the absorber can be identified with a dusty, clumpy torus. The absorption variability time-scale enables us to locate the X-ray-emitting region within the innermost ˜50 gravitational radii. Such result holds not only for the X-ray continuum, but also for the soft excess. [less ▲]

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See detailThe size of the X-ray emitting region in SWIFT J2127.4+5654 via a broad line region cloud X-ray eclipse
Sanfrutos, M.; Miniutti, G.; Agis-Gonzalez, Beatriz ULiege et al

in Monthly Notices of the Royal Astronomical Society (2013), 436

We present results obtained from the time-resolved X-ray spectral analysis of the Narrow-Line-Seyfert 1 galaxy SWIFT J2127.4+5654 during a ˜130 ks XMM-Newton observation. We reveal large spectral ... [more ▼]

We present results obtained from the time-resolved X-ray spectral analysis of the Narrow-Line-Seyfert 1 galaxy SWIFT J2127.4+5654 during a ˜130 ks XMM-Newton observation. We reveal large spectral variations, especially during the first ˜90 ks of the XMM-Newton exposure. The spectral variability can be attributed to a partial eclipse of the X-ray source by an intervening low-ionization/cold absorbing structure (cloud) with column density N[SUB]H[/SUB] = 2.0^{+0.2}_{-0.3}× 10^{22} cm[SUP]-2[/SUP] which gradually covers and then uncovers the X-ray emitting region with covering fraction ranging from zero to ˜43 per cent. Our analysis enables us to constrain the size, number density and location of the absorbing cloud with good accuracy. We infer a cloud size (diameter) of D[SUB]c[/SUB] ≤ 1.5 × 10[SUP]13[/SUP] cm, corresponding to a density of n[SUB]c[/SUB] ≥ 1.5 × 10[SUP]9[/SUP] cm[SUP]-3[/SUP] at a distance of R[SUB]c[/SUB] ≥ 4.3 × 10[SUP]16[/SUP] cm from the central black hole. All of the inferred quantities concur to identify the absorbing structure with one single cloud associated with the broad line region of SWIFT J2127.4+5654. We are also able to constrain the X-ray emitting region size (diameter) to be D[SUB]s[/SUB] ≤ 2.3 × 10[SUP]13[/SUP] cm which, assuming the black hole mass estimated from single-epoch optical spectroscopy (1.5 × 10[SUP]7[/SUP] M[SUB]⊙[/SUB]), translates into D[SUB]s[/SUB] ≤ 10.5 gravitational radii (r[SUB]g[/SUB]) with larger sizes (in r[SUB]g[/SUB]) being associated with smaller black hole masses, and vice versa. We also confirm the presence of a relativistically distorted reflection component off the inner accretion disc giving rise to a broad relativistic Fe K emission line and small soft excess (small because of the high Galactic column density), supporting the measurement of an intermediate black hole spin in SWIFT J2127.4+5654 that was obtained from a previous Suzaku observation. [less ▲]

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