Related papers: 1H0419-577: a two-state Seyfert Galaxy?
BeppoSAX observed the low-luminous Seyfert 1 Galaxy NGC4051 in a ultra-dim X-ray state. The 2-10 keV flux (1.26 x 10^{-12} erg/cm^2/s) was about 20 times fainter than its historical average value, and remained steady along the whole…
We report on soft X-ray observations of the Seyfert 1 galaxy MCG-6-30-15 with the Low and Medium Energy Concentrator Spectrometers on board BeppoSAX. The time averaged 0.1-4 keV spectrum shows evidence for a complex warm absorber. K-edges…
We present preliminary results from a long Chandra HETG observation of the luminous Narrow-line Seyfert 1 galaxy 1H 0707-495. We find a complex X-ray spectrum comprised of a two-component continuum with superimposed emission and absorption…
We report on the first spectrum up to 10 keV of the bright narrow-line Seyfert 1 galaxy Ton S 180, obtained with the imaging instruments onboard BeppoSAX. This is the first observed source in a sample of a dozen narrow-line Seyfert 1…
In the present work we report the BeppoSAX observation of the Seyfert 1.9 galaxy NGC 526A in the band 0.1-150 keV. The high energy instrument onboard, PDS, has succeeded in measuring for the first time the spectrum of this source in the…
We report on our analysis of XMM-Newton observations of the Seyfert 2 galaxy ESO 138-G1 (z = 0.0091). These data reveal a complex spectrum in both its soft and hard portions. The 0.5-2 keV band is characterized by a strong 'soft-excess'…
Thirty years ago the optical counterpart of the x-ray source 1H0707-495 was discovered to be a 15th magnitude broad-line Seyfert galaxy with a rich Fe II emission line spectrum typical of the AGN subclass sometimes referred to as the I Zw 1…
BeppoSAX observed NGC4258 on December 1998, when its 2-10 keV luminosity was \~1E41 erg/s. 100% variability is observed in the 3-10 keV band on timescales of a half a day while 20% variability is observed on timescales of one hour. The…
BeppoSAX observations of Broad Line Radio Galaxies (BLRGs) have shown that they have a considerable variety of spectral properties and important differences with respect to their radio-quiet counter-part Seyfert 1s. In radio galaxies the…
A large sample of AGN studied here shows a ``quenching'' of the radio emission occurs when the luminosity is at a few percent to about 10% of the Eddington rate, just as is seen in the high/soft state of X-ray binaries. The result holds…
We present results from BeppoSAX observations of 10 low redshift quasars. The quasars are part of the Laor et al. (1997) sample of 23 optically selected PG quasars with redshift <0.4 and low Galactic absorption along the line of sight.…
This paper reports the X-ray spectral analysis of 5 high-redshift (z \ge 2) radio-quiet quasars observed by ASCA. A simple power law continuum plus cold Galactic absorption model well fits all the spectra (tipically between $\sim$ 2-30 keV…
We present preliminary results from two observations of the radio galaxy Centaurus A performed by the BeppoSAX satellite. We did not detect any spectral variation of the nuclear continuum in spite of the long-term flux change (by a factor…
We present preliminary results of the spectral analysis of a large sample of Seyfert galaxies observed by BeppoSAX. The only selection criterium was a sufficiently large S/N ratio (>10) in the PDS band (12-200 keV) to allow good detection…
We present the main results of broad band (0.1-10 keV) BeppoSAX observations of a selected sample of Narrow Line Seyfert 1 galaxies (NLS1s). We have performed a spectroscopic analysis of LECS and MECS data to test their average spectral…
We present preliminary results of the long term spectral monitoring of two active galactic nuclei with different broad line shapes: Ark 564 and Arp 102B. Ark 564 is a bright nearby narrow line Syfert 1 (NLS1) galaxy with relatively narrow…
We present preliminary results of the X-ray analysis of XMM-Newton and Swift observations as part of a multi-wavelength monitoring campaign in 2012 of the radio-loud narrow line Seyfert 1 galaxy PKS 2004-447. The source was recently…
Based on a deep survey of the Galactic Center region performed with the INTEGRAL observatory, we measured for the first time the hard X-ray (20-200 keV) spectrum of the Seyfert 1 galaxy GRS 1734-292 located in the direction of the Galactic…
In this work we present the first of two papers devoted to the study of the X-ray spectral characteristics of Seyfert 1 galaxies in the Piccinotti sample. In particular we analyse here the BeppoSAX broad band (0.1-100 keV) data of 4 objects…
Seyfert-type AGN that exhibit unusually strong and steep soft X-ray spectra are reviewed, building on observations made during the ROSAT all-sky survey. Two individual cases are described in brief detail, both being identified initially in…