Search Publications
Fe K emission in the ultraluminous infrared galaxy Arp 220
Sanders, D. B.; Iwasawa, K.; Miniutti, G. +3 more
Prominent Fe Kα line emission is detected in the XMM-Newton spectrum of the ultraluminous infrared galaxy Arp 220. The centroid of the line is found at an energy of 6.7 keV and the equivalent width of the line is EW ~ 1.9 keV (at 3.5σ significance). A few other spectral features are found at various degrees of significance in the lower energy rang…
Submillimetre photometry of X-ray absorbed quasi-stellar objects: their formation and evolutionary status
Ivison, R. J.; Smail, Ian; Page, M. J. +4 more
We present an analysis of the submillimetre/X-ray properties of 19 X-ray absorbed, Compton-thin quasi-stellar objects (QSOs) selected to have luminosities and redshifts that represent the peak of cosmic QSO activity, i.e. ~L* objects at 1 < z < 3. Of these, we present new data for 11 objects not previously observed at submillimetre wavelengt…
The XMM Large-Scale Structure survey: an initial sample of galaxy groups and clusters to a redshift z < 0.6*
Altieri, B.; Valtchanov, I.; Pierre, M. +14 more
We present X-ray and optical spectroscopic observations of 12 galaxy groups and clusters identified within the X-ray Multi-Mirror (XMM) Large-Scale Structure (LSS) survey. Groups and clusters are selected as extended X-ray sources from a 3.5 deg2XMM image mosaic above a flux limit 8 × 10-15 erg s-1 cm-2 …
FeXXV and FeXXVI lines from low-velocity, photoionized gas in the X-ray spectra of active galactic nuclei
Nicastro, Fabrizio; Bianchi, Stefano; Matt, Giorgio +2 more
We have calculated the equivalent widths of the absorption lines produced by FeXXV and FeXXVI in a Compton-thin, low-velocity photoionized material illuminated by the nuclear continuum in active galactic nuclei. The results, plotted against the ionization parameter and the column density of the gas, are a complement to those presented by Bianchi &…
The extended Hα-emitting filaments surrounding NGC 4696, the central galaxy of the Centaurus cluster
Fabian, A. C.; Sanders, J. S.; Crawford, C. S. +1 more
We present images of NGC 4696, the central galaxy in the Centaurus cluster, showing the large extent of cool filaments that are bright in Hα line emission. These filaments share the detailed structure of both the central dust lane and the inner regions of the arc-like plumes seen in soft X-ray emission. The X-ray gas is at its coolest and most abs…
The Hubble constant from the gravitational lens CLASS B0218+357 using the Advanced Camera for Surveys
Jackson, N.; Browne, I. W. A.; York, T. +2 more
We present deep optical observations of the gravitational lens system CLASS B0218+357, from which we derive an estimate for the Hubble constant (H0). Extensive radio observations using the VLA, MERLIN, the VLBA and VLBI have reduced the degeneracies between H0 and the mass model parameters in this lens to one involving only t…
The XMM-Newton view of Mrk 3 and IXO 30
Fabian, Andrew C.; Bianchi, Stefano; Miniutti, Giovanni +1 more
We present the analysis of the XMM-Newton European Photon Imaging Camera (EPIC) pn spectrum of the Seyfert 2 galaxy Mrk 3. We confirm that the source is dominated by a pure Compton reflection component and an iron Kα line, both produced as a reflection from a Compton-thick torus, likely responsible also for the large column density (1.36+0.03…
High-mass X-ray binaries in the Small Magellanic Cloud: the luminosity function
Gilfanov, M.; Shtykovskiy, P.
We study a population of compact X-ray sources in the Small Magellanic Cloud (SMC) using archival data from the XMM-Newton observatory. The total area of the survey is ~1.5 deg2 with the limiting sensitivity of ~10-14 erg s-1 cm-2, corresponding to a luminosity of ~4.3 × 1033 erg s-1
Hubble Space Telescope ultraviolet spectroscopy of blazars: emission-line properties and black hole masses
Pian, E.; Falomo, R.; Treves, A.
The ultraviolet (UV) spectra of 16 blazars (<z>~= 1) from the archives of the Hubble Space Telescope Faint Object Spectrograph have been analysed in order to study in a systematic way the properties of their broad UV emission lines. We find that the luminosities of the most prominent and intense lines, Lyα and CIVλ1549, are similar to those …
On the transmission-dominated to reprocessing-dominated spectral state transitions in Seyfert 2 galaxies
Fiore, F.; Guainazzi, M.; Iwasawa, K. +2 more
We present Chandra and XMM-Newton observations of a small sample (11 objects) of optically selected Seyfert 2 galaxies, for which ASCA and BeppoSAX had suggested Compton-thick obscuration of the active galactic nucleus (AGN). The main goal of this study is to estimate the rate of transitions between `transmission-dominated' and `reprocessing-domin…