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Winds outflowing from Active Galactic Nuclei (AGNs) may carry significant amount of mass and energy out to their host galaxies. In this paper we report the detection of a sub-relativistic outflow observed in the Narrow Line Seyfert 1 Galaxy…

We present the results obtained from broadband spectroscopy of the high mass X-ray binary 4U 1700-37 using data from a Suzaku observation in 2006 September 13-14 covering 0.29-0.72 orbital phase range. The light curves showed significant…

We report on the analysis of a long XMM-Newton EPIC observation in 2001 May of the Narrow Line Seyfert 1 galaxy Mkn 766. The 3-11 keV spectrum exhibits a moderately steep power law continuum, with a broad emission line at ~6.7 keV, probably…

We report the first detection of a sharp spectral feature in a Narrow-Line Seyfert 1 galaxy. Using XMM-Newton we have observed 1H0707-495 and find a drop in flux by a factor of more than 2 at a rest-frame energy of ~7 keV without any…

We observed the Seyfert 1 galaxy NGC 985 on multiple occasions to search for variability in its UV and X-ray absorption features in order to establish their location and physical properties. We use XMM-Newton to obtain X-ray spectra using…

We present an X-ray spectral analysis of 21 low redshift quasars observed with XMM-Newton EPIC. All the sources are Palomar Green quasars with redshifts between 0.05 and 0.4 and have low Galactic absorption along the line-of-sight. A large…

Long-exposure Suzaku X-ray observations of the active galaxy NGC 4051 from 2005 and 2008 are analysed, in an attempt to reach a self-consistent understanding of the spectral variability on long timescales and at high time resolution.…

We present an accurate analysis of the H2 absorption lines from the zabs ~ 2.4018 damped Ly{\alpha} system towards HE 0027-1836 observed with the Very Large Telescope Ultraviolet and Visual Echelle Spectrograph (VLT/UVES) as a part of the…

In this paper, we provide new 1 Ms $Chandra$ ACIS spectra of two quasars in the Chandra Deep Field South (CDF-S), which were previously reported to show strong and extremely blueshifted X-ray emission/absorption line features in previous 1…

We present Suzaku observations of five hard X-ray selected nearby Seyfert 2 galaxies. All the sources were clearly detected with the pin Hard X-ray Detector up to several tens of keV, allowing for a fairly good characterization of the…

We present joint NuSTAR and XMM-Newton observations of the bright, variable quasar IRAS 13349+2438. This combined dataset shows two clear iron absorption lines at 8 and 9 keV, which are most likely associated with two layers of mildly…

The narrow-line quasar PHL 1092 was observed by XMM-Newton at two epochs separated by nearly thirty months. Timing analyses confirm the extreme variability observed during previous X-ray missions. A measurement of the radiative efficiency…

The origin of the soft excess seen in many AGN below ~1 keV is still an unsolved problem. It is unlikely to represent a true continuum component as its characteristic 'temperature' shows a remarkable constancy over a wide range of AGN…

We report the initial result of an adaptive-optics assisted, optical integral-field-unit observation on IRAS04576+0912, the nearest (z=0.039) active galactic nucleus with a prominent blueshift/tail in [O III] emission from a sample of such…

X-ray absorption line spectroscopy has recently shown evidence for previously unknown Ultra-fast Outflows (UFOs) in radio-quiet AGNs. In the previous paper of this series we defined UFOs as those absorbers with an outflow velocity higher…

We report the timing and broad-band spectral properties of the Be transient high mass X-ray binary pulsar GRO J1008-57 using a Suzaku observation in the declining phase of its 2007 November-December outburst. Pulsations with a period of…

Aims. We seek a comprehensive analysis of all the information provided by the XMM-Newton satellite of the four Seyfert 1 galaxies ESO 359-G19, HE 1143-1810, CTS A08.12, and Mrk 110, including the UV range, to characterize the different…

The Seyfert Galaxy Mrk 335 is known for its frequent changes of flux and spectral shape in the X-ray band occurred during recent years. These variations may be explained by the onset of a wind that previous, non-contemporaneous…

Recent radiation-magnetohydrodynamic simulations of active galactic nuclei predict the presence of the disk winds, which may get unstable and turn into fragmented clumps far from the central black hole. These inner winds and the outer…

We assess the cosmological variability of the fine-structure constant from the analysis of an ensemble of Fe II absorption lines at the redshift z=1.15 toward the QSO HE 0515-4414 by means of the standard many-multiplet (MM) technique and…