The standard model of Active Galactic Nuclei (AGNs) predicts that Type 2
AGNs and Type 1 AGNs only differ in the orientation of a dust torus,
which does or does not allow one to observe the central region. If the
model is correct, the time-scales and the amplitudes of observed
temporal variations should be different between obscured and unobscured
objects. In order to test this hypothesis, we started a multi-wavelength
(BRIJK<SUB>s</SUB>) monitoring campaign of a sample of quasars of both
types. Here we present the data and preliminary results of that project.
Table presents the X-ray properties of all 1121 objects, including
fluxes in six selected energy bands, and public available optical data
for X-ray counterparts. X-ray flux in X/O flux ratio is the sum of
fluxes in (0.5-2keV) and (2-4.5keV) bands, while the optical flux
corresponds to R band. The represented hardness ratio was set using the
same X-ray bands. Photometric redshifts and K-corrections were measured
using the photometric information in five optical (Furusawa et al.,
2008, Cat. J/ApJS/176/1), three NIR (Hewett et al., 2006MNRAS.367..454H;
Hodgkin et al.,...
The analysis of the physical properties of low-redshift Lyα
emitters (LAEs) can provide clues in the study of their high-redshift
analogs. At z ~ 0.3, LAEs are bright enough to be detected over almost
the entire electromagnetic spectrum and it is possible to carry out a
more precise and complete study than at higher redshifts. In this work,
we examine the UV and IR emission, dust attenuation, star formation rate
(SFR), and morphology of a sample of 23 GALEX-discovered star-forming
LAEs at z ~ 0.3 with direct UV (GALEX), optical (ACS), and FIR (PACS and
MIPS) data. Using the same UV...
We have started a project to investigate the connection of post-novae
with the population of cataclysmic variables (CVs). Our first steps in
this concern improving the sample of known post-novae and their
properties. Here we present the recovery and/or confirmation of the old
novae MT Cen, V812 Cen, V655 CrA, IL Nor, V2109 Oph, V909 Sgr, V2572 Sgr
and V728 Sco. Principal photometric and spectroscopic properties of
these systems are discussed. We find that V909 Sgr is a probable
magnetic CV, and that V728 Sco is a high-inclination system. We
furthermore suggest that the two candidate...
Context. The connection between active galactic nuclei (AGN) and their
host galaxies has been widely studied and found to be of great
importance for providing answers to some fundamental questions related
to AGN fuelling mechanisms, and both their formation and evolution. <BR
/> Aims: Using X-ray data and one of the deepest broad-band optical data
sets available, we study how morphology and colours are related to X-ray
properties for sources at redshifts z ≤ 2.0, using a sample of 262
AGN in the Subaru/XMM-Newton Deep Survey (SXDS). <BR /> Methods: We
performed our morphological...
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