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Fe emission and ionized excess absorption in the luminous quasar 3C 109 with XMM-Newton
Fabian, A. C.; Miniutti, G.; Ross, R. R. +2 more
We report results from an XMM-Newton observation of the broad-line radio galaxy 3C 109 (z = 0.3056). Previous ASCA data revealed the presence of a broad iron line from the accretion disc with which the XMM-Newton spectrum is fully consistent. However, although improving the ASCA constraints on the line parameters, the quality of the data is not hi…
The ultraluminous X-ray sources in the high-velocity system of NGC1275
Fabian, A. C.; Sanders, J. S.; González-Martín, O.
We report the results of a study of X-ray point sources coincident with the high-velocity system (HVS) projected in front of NGC1275. A very deep X-ray image of the core of the Perseus cluster, made with the Chandra X-ray Observatory, has been used. We find a population of ultraluminous X-ray sources [ULXs seven sources with LX(0.5 - 7.…
Composite spectra Paper 14: HR 1129, a long-period binary showing evidence of circumbinary material
Stickland, D. J.; Griffin, R. E. M.; Griffin, R. F.
HR 1129 is a 4.8-mag star in the constellation Camelopardus, strangely (in view of its brightness) lacking a constellation designation. It has long been known to exhibit a composite spectrum consisting of a late-type primary and an early-type secondary. The radial velocity of the primary is easily measured, and was announced as variable nearly 100…
XMM-Newton and Chandra observations of SHEEP sources
Georgakakis, A.; Nandra, K.; Papadakis, I. E. +3 more
We present Chandra and XMM-Newton observations of 12 bright [f(2-10keV) > 10-13ergcm-2s-1] sources from the ASCA search for the High Energy Extragalactic Population (SHEEP) survey. Most of these have been either not observed or not detected previously with the ROSAT mission, and therefore they constitute a sampl…
A comprehensive range of X-ray ionized-reflection models
Fabian, A. C.; Ross, R. R.
X-ray ionized reflection occurs when a surface is irradiated with X-rays so intense that its ionization state is determined by the ionization parameter ξ~F/n, where F is the incident flux and n the gas density. It occurs in accretion, on to compact objects including black holes in both active galaxies and stellar-mass binaries, and possibly in gam…
A Hubble Space Telescope lensing survey of X-ray luminous galaxy clusters - IV. Mass, structure and thermodynamics of cluster cores at z= 0.2
Smith, Graham P.; Smail, Ian; Kneib, Jean-Paul +3 more
We present a comprehensive space-based study of 10 X-ray luminous galaxy clusters (LX>= 8 × 1044 erg s-1, 0.1-2.4 keV) at z= 0.2. Hubble Space Telescope (HST) observations reveal numerous gravitationally lensed arcs for which we present four new spectroscopic redshifts, bringing the total to 13 confirmed arcs in…
What controls the CIV line profile in active galactic nuclei?
Laor, Ari; Baskin, Alexei
The high-ionization lines in active galactic nuclei (AGN), such as CIV, tend to be blueshifted with respect to the lower-ionization lines, such as Hβ, and often show a strong blue excess asymmetry not seen in the low-ionization lines. There is accumulating evidence that the Hβ profile is dominated by gravity, and thus provides a useful estimate of…
The unresolved hard X-ray background: the missing source population implied by the Chandra and XMM-Newton deep fields
Alexander, D. M.; Bauer, F. E.; Brandt, W. N. +6 more
We extend our earlier work on X-ray source stacking in the deep XMM-Newton observation of the Lockman Hole, to the 2-Ms Chandra Deep Field North (CDF-N) and the 1-Ms Chandra Deep Field South (CDF-S). The XMM-Newton work showed the resolved fraction of the X-ray background (XRB) to be ~80-100 per cent at <~ 2keV but this decreased to only ~50 pe…
Multicomponent decompositions for a sample of S0 galaxies
Salo, Heikki; Laurikainen, Eija; Buta, Ronald
We have estimated the bulge-to-total (B/T) light ratios in the Ks band for a sample of 24 S0, S0/a and Sa galaxies by applying a two-dimensional multicomponent decomposition method. For the disc an exponential function is used, the bulges are fitted by a Sérsic R1/n function and the bars and ovals are described either by a Sé…
How large are the bars in barred galaxies?
Erwin, Peter
I present a study of the sizes (semimajor axes) of bars in disc galaxies, combining a detailed R-band study of 65 S0-Sb galaxies with the B-band measurements of 70 Sb-Sd galaxies from Martin (1995). As has been noted before with smaller samples, bars in early-type (S0-Sb) galaxies are clearly larger than bars in late-type (Sc-Sd) galaxies; this is…