340 research outputs found
Six years of BeppoSAX observations of blazars: a spectral catalog
We present a spectral catalog for blazars based on the BeppoSAX archive. The
sample includes 44 High-energy peaked BL Lacs (HBLs), 14 Low-energy peaked BL
Lacs (LBLs), and 28 Flat Spectrum Radio Quasars (FSRQs). A total of 168 LECS,
MECS, and PDS spectra were analyzed, corresponding to observations taken in the
period 1996--2002. The 0.1--50 keV continuum of LBLs and FSRQs is generally
fitted by a single power law with Galactic column density. A minority of the
observations of LBLs (25%) and FSRQs (15%) is best fitted by more complex
models like the broken power law or the continuously curved parabola. These
latter models provide also the best description for half of the HBL spectra.
Complex models are more frequently required for sources with fluxes F_{2-10
keV} > 10^-11 cm-2 s-1, corresponding to spectra with higher signal-to-noise
ratio. As a result, considering sources with flux above this threshold, the
percentage of spectra requiring those models increases for all the classes. We
note that there is a net separation of X-ray spectral properties between HBLs
on one side, and LBLs and FSRQs on the other, the distinction between LBLs and
FSRQs is more blurry. This is most likely related to ambiguities in the optical
classification of the two classes.Comment: 6 pages, 4 figures, 7 tables. Accepted for publication in A&
Evidence for a circum-nuclear and ionised absorber in the X-ray obscured BroadLine Radio Galaxy 3C 445
Here we present the results of a Suzaku observation of the Broad Line Radio
Galaxy 3C 445. We confirm the results obtained with the previous X-ray
observations which unveiled the presence of several soft X-ray emission lines
and an overall X-ray emission which strongly resembles a typical Seyfert 2
despite of the optical classification as an unobscured AGN. The broad band
spectrum allowed us to measure for the first time the amount of reflection
(R~0.9) which together with the relatively strong neutral Fe Kalpha emission
line (EW ~ 100 eV) strongly supports a scenario where a Compton-thick mirror is
present. The primary X-ray continuum is strongly obscured by an absorber with a
column density of NH =2-3 x10^{23} cm^{-2}. Two possible scenarios are proposed
for the absorber: a neutral partial covering or a mildly ionised absorber with
an ionisation parameter log\xi ~ 1.0 erg cm s^{-1}. A comparison with the past
and more recent X-ray observations of 3C 445 performed with XMM-Newton and
Chandra is presented, which provided tentative evidence that the ionised and
outflowing absorber varied. We argue that the absorber is probably associated
with an equatorial disk-wind located within the parsec scale molecular torus.Comment: Accepted by MNRAS; 13 pages, 6 figures, 4 table
Chandra detection of a parsec scale wind in the Broad Line Radio Galaxy 3C 382
We present unambiguous evidence for a parsec scale wind in the Broad-Line
Radio Galaxy (BLRG) 3C 382, the first radio-loud AGN, with , whereby an outflow has been measured with
X-ray grating spectroscopy. A 118 ks Chandra grating (HETG) observation of 3C
382 has revealed the presence of several high ionization absorption lines in
the soft X-ray band, from Fe, Ne, Mg and Si. The absorption lines are
blue-shifted with respect to the systemic velocity of 3C 382 by -840\pm60 km/s
and are resolved by Chandra with a velocity width of 340\pm70 km/s. The outflow
appears to originate from a single zone of gas of column density cm and ionization parameter . From
the above measurements we calculate that the outflow is observed on parsec
scales, within the likely range from 10-1000 pc, i.e., consistent with an
origin in the Narrow Line Region.Comment: 11 pages, accepted for publication in Astrophysical Journal Letter
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