Related papers: On the warm absorber in AGN outflow
High resolution X-ray spectroscopy of the warm absorber in the nearby X-ray bright Seyfert 1 galaxy, Mrk 1040 is presented. The observations were carried out in the 2013-2014 timeframe using the Chandra High Energy Transmission Grating with…
Signatures of warm absorbers are seen in soft X-ray spectra of about half of all Seyfert1 galaxies observed and in some quasars and blazars. We use the thermal equilibrium curve to study the influence of the shape of the ionizing continuum,…
Warm absorbers are an important new probe of the central regions of active galaxies. So far, they revealed their existence mainly in the soft X-ray spectral region. In observing and modeling this component, we can learn a lot about the…
In about half of Seyfert galaxies, the X-ray emission is absorbed by an optically thin, ionized medium, the so-called "Warm Absorber", whose origin and location is still a matter of debate. The aims of this paper is to put more constraints…
Warm absorbers and related phenomena are one of the observable manifestations of outflows or winds from active galactic nuclei (AGN). Warm absorbers are common in low luminosity AGN, they have been extensively studied observationally, and…
The existence of ionized X-ray absorbing layers of gas along the line of sight to the nuclei of Seyfert galaxies is a well established observational fact. This material is systematically outflowing and shows a large range in parameters.…
Seyfert galaxies have been shown to exhibit a large variety of features in their X-ray spectra from which the environment of the central engine can be deduced. We focus on the two following aspects: the Warm Absorber, mainly responsible of…
The analysis of X-ray absorption features in active galactic nuclei (AGN) provides a wealth of information about the physical properties of the matter surrounding supermassive black holes (SMBHs). While standard correlations between the…
We present a time-resolved X-ray spectral analysis of the warm absorbers in the Seyfert galaxy NGC 4051, which has an active galactic nucleus (AGN), using observations from the Neutron Star Interior Composition Explorer (NICER). Despite…
Warm absorber spectra contain bound-bound and bound-free absorption features seen in the X-ray and UV spectra from many active galactic nuclei (AGN). The widths and centroid energies of these features indicate they occur in outflowing gas,…
The aim of this paper is to study the variability of the warm absorber "clouds of ionised gas within AGN", for the Seyfert 1 galaxies Arakelian 564. The X-ray spectra for four XMM-Newton observations of this object are analysed in EPIC and…
The relation between warm absorber (WA) outflows of AGN and nuclear obscuration activities caused by optically-thick clouds (obscurers) crossing the line of sight is unclear. NGC 3227 is a suitable target to study the properties of both WAs…
We present a new method to model a HST/COS spectrum, aimed to analyze intrinsic UV absorption from the outflow of Mrk 290, a Seyfert I galaxy. We use newly updated XSTAR to generate photoionization models for the intrinsic absorption from…
The radiation from the central regions of active galactic nuclei, including that from the accretion disk surrounding the black hole, is likely to peak in the extreme ultraviolet $\sim 13 -100$ eV. However, due to Galactic absorption, we are…
We report on the performance of the statistical, X-ray absorption lines identification procedure XLINE-ID. As illustration, it is used to estimate the time averaged gas density $n_H(r)$ of a representative AGN's warm absorber ($T\approx…
We present soft X-ray results from observations with the Chandra HETGS of the Seyfert I AGN NGC 4593 and Mrk 509. We discuss the photoionized outflows associated with Seyfert I AGN in terms of their absorption spectral signatures and…
A hydromagnetic (MHD) wind from a clumpy molecular accretion disk is invoked to explain observations of warm absorbing (WA) gas in UVX from Sy galaxies. This paper focuses on two issues: (1) compatibility of kinematics and dynamics of MHD…
We investigated, using spectral-timing analysis, the characterization of highly ionized outflows in Seyfert galaxies, the so-called warm absorbers. Here, we present our results on the extensive ~ 600 ks of XMM-Newton archival observations…
We study the variability of the warm absorber and the gas responsible for the emission lines in the Seyfert 1 galaxy NGC 5548, in order to constrain the location and physical properties of these components. Using X-ray spectra taken with…
We present a XMM-Newton observation of Markarian 304, a Seyfert 1 galaxy at z = 0.066. The EPIC data show that MKN 304 is affected by heavy (Nh ~10^{23} cm{-2}) obscuration due to ionized gas. A two-phase warm absorber provides an adequate…