386 citations · 4.7k across the 101 of their papers we have counts for
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PHL 1092 as a transient extreme X-ray weak quasar
G. Miniutti, A. C. Fabian, W. N. Brandt +2
We report a dramatic variability event in the X-ray history of the Narrow-Line quasar PHL 1092 (z=0.396). Our latest 2008 XMM-Newton observation reveals a flux drop of ~200 with re…
Interpreting the Transmission Windows of Distant Quasars
A. Maselli, A. Ferrara, S. Gallerani
We propose the Apparent Shrinking Criterion (ASC) to interpret the spatial extent, R_w, of transmitted flux windows in the absorption spectra of high-z quasars. The ASC can discrim…
Parsec-scale dust distributions in Seyfert galaxies - Results of the MIDI AGN snapshot survey
Konrad R. W. Tristram, David Raban, Klaus Meisenheimer +11
The emission of warm dust dominates the mid-infrared spectra of active galactic nuclei (AGN). Only interferometric observations provide the necessary angular resolution to resolve…
Multi-wavelength data handling in current and future surveys: the possible role of Virtual Observatory
C. Vignali, F. Fiore, A. Comastri +5
Here we review some of the main issues related to multi-wavelength source identification and characterization, with particular emphasis on the field of X-ray surveys carried out ov…