1,087 research outputs found
Mkn 1239: A highly polarized NLS1 with a steep X-ray spectrum and strong NeIX emission
We report the results of an XMM-Newton observation of the Narrow-Line Seyfert
1 galaxy Mkn 1239. This optically highly polarized AGN has one of the steepest
X-ray spectra found in AGN with alpha-X = +3.0 based on ROSAT PSPC data. The
XMM-Newton EPIC PN and MOS data confirm this steep X-ray spectrum. The PN data
are best-fit by a powerlaw with a partial covering absorption model suggesting
two light paths between the continuum source and the observer, one indirect
scattered one which is less absorbed and a highly absorbed direct light path.
This result agrees with the wavelength dependent degree of polarization in the
optical/UV band. Residuals in the X-ray spectra of all three XMM-Newton EPIC
detectors around 0.9 keV suggest the presence of an emission line feature, most
likely the Ne IX triplet. The detection of NeIX and the non-detection of
OVII/OVIII suggest a super-solar Ne/O ratio.Comment: Submitted to Aj, 11 pages, 8 figue
Analysing the Suzaku Spectra of the Broad-Line Seyfert 1 Galaxy CBS 126
We analysed new simultaneous \emph{Suzaku} and \emph{Swift} data of the Broad
Line Seyfert 1 (BLS1) galaxy CBS 126. A clear Fe emission line and a strong
soft excess are present in the source spectra. We fit the spectra with a
relativistic reflection model and find the model tends to fit the data with a
high iron abundance possibly due to the large soft excess present. By checking
the difference and the RMS spectra, we find there is likely an absorption edge
at 0.89 keV, which might be caused by oxygen or neon. We also produced
an analysis of the time-resolved spectra in order to examine the existence of
the edge. Although high iron abundance is required more in the time-resolved
spectra, a model of solar iron abundance together with an absorption edge gives
a more physical explanation. Variation of the ionisation parameter is an
alternative, plausible explanation for the excess seen in the difference
spectra. It is difficult to know if there are warm absorbers in this source
from the current data. To further investigate the presence of possible warm
absorbers, higher signal-to-noise low-energy data are needed. The work
presented here tentatively suggests that the spectra of a BLS1 can be explained
by a relativistic reflection model similar to that often seen in their
narrow-line cousins.Comment: 10 pages, 12 figures, accepted for publication in MNRA
Seyfert galaxies with Swift: giant flares, rapid drops, and other surprises
Swift has initiated a new era of understanding the extremes of active
galactic nuclei (AGN) variability, their drivers and underlying physics. This
is based on its rapid response, high sensitivity, good spatial resolution, and
its ability to collect simultaneously X--ray-to-optical SEDs. Here, we present
results from our recent monitoring campaigns with Swift of highly variable AGN,
including outbursts, deep low states, and unusual long-term trends in several
Seyfert galaxies including Mrk 335, WPVS007, and RXJ2314.9+2243. We also report
detection of a new X-ray and optical outburst of IC 3599 and our Swift
follow-ups. IC 3599 was previously known as one of the AGN with the
highest-amplitude outbursts. We briefly discuss implications of this second
outburst of IC 3599 for emission scenarios including accretion-disk
variability, repeat tidal disruption events, and the presence of a binary
supermassive black hole.Comment: to appear in "Swift: 10 years of discovery", Proceedings of Scienc
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