相关论文: X-ray evidence for ultra-fast outflows in local AG…
Recent X-ray observations show absorbing winds with velocities up to mildly-relativistic values of the order of ~0.1c in a limited sample of 6 broad-line radio galaxies. They are observed as blue-shifted Fe XXV-XXVI K-shell absorption…
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 present the results of a uniform and systematic search for blue-shifted Fe K absorption lines in the X-ray spectra of five bright Broad-Line Radio Galaxies (BLRGs) observed with Suzaku. We detect, for the first time at X-rays in…
Ultra-fast outflows (UFOs) are mildly relativistic (outflow velocity $v_{out}>0.1c$) nuclear winds detected as blueshifted absorption lines from highly ionized, dense gas in the X-ray spectra of active galactic nuclei. The AGN feedback…
Using the results of a previous X-ray photo-ionization modelling of blue-shifted Fe K absorption lines on a sample of 42 local radio-quiet AGNs observed with XMM-Newton, in this letter we estimate the location and energetics of the…
Ultra-fast outflows (UFOs) are highly ionized, mildly relativistic winds seen in the X-ray spectra of active galactic nuclei (AGN) and are thought to contribute to AGN feedback and galaxy evolution. We investigate UFO signatures by…
Relativistically blueshifted absorption features of highly ionised ions, the so-called ultra-fast outflows (UFOs), have been detected in the X-ray spectra of a number of accreting supermassive black holes. If these features truly originate…
We performed a blind search for narrow absorption features at energies greater than 6.4 keV in a sample of 42 radio-quiet AGNs observed with XMM-Newton. We detect 36 narrow absorption lines on a total of 101 XMM-Newton EPIC pn observations.…
Ultrafast outflows (UFOs) are the most extreme winds launched by active galactic nuclei (AGN) due to their mildly-relativistic speeds (~0.1-0.3c) and are thought to significantly contribute to galactic evolution via AGN feedback. Their…
Previous X-ray spectral analysis has revealed an increasing number of AGNs with high accretion rates where an outflow with a mildly relativistic velocity originates from the inner accretion disk. Here we report the detection of a new…
We present a qualitative search for ultra-fast outflows (UFOs) in excess variance spectra of radio-quiet active galactic nuclei (AGN). We analyse 42 sources from the Tombesi et al. (2010) spectroscopic UFO detection sample, and an…
Ultra Fast Outflows (UFOs) are powerful, highly ionized winds launched from the innermost regions of Active Galactic Nuclei (AGNs), reaching velocities of 0.03 -- 0.3 c and playing a key role in AGN feedback. We present a photoionization…
The detection of blue-shifted absorption lines likely associated with ionized Iron K-shell transitions in the X-ray spectra of many Active Galactic Nuclei (AGN) suggests the presence of a highly ionized gas outflowing with mildly…
Ultrafast outflows (UFOs) have recently been found in the spectra of a number of active galactic nuclei (AGN) and are strong candidates for driving AGN feedback. 1H0707-495 is a highly accreting narrow line Seyfert 1 and the second most…
During the last decade, strong observational evidence has been accumulated for the existence of massive, high velocity winds/outflows (aka Ultra Fast Outflows, UFOs) in nearby AGNs and in more distant quasars. Here we briefly review some of…
XMM-Newton and Suzaku spectra of AGN have revealed highly ionized gas, in the form of absorption lines from H-like and He-like Fe. Some of these absorbers, "Ultra Fast Outflows (UFOs)", have radial velocities of up to 0.25c. We have…
The extreme velocities and high ionization states of ultra-fast outflows (UFOs) make them a promising candidate for AGN feedback on the evolution of the host galaxy. However, their exact underlying driving mechanism is not yet fully…
Using two-dimensional radiation hydrodynamic simulations, we investigate origin of the ultra fast outflows (UFOs) that are often observed in luminous active galactic nuclei (AGNs). We found that the radiation force due to the spectral lines…
The study of winds in active galactic nuclei (AGN) is of utmost importance as they may provide the long sought-after link between the central black hole and the host galaxy, establishing the AGN feedback. Recently, Laha et al. (2014)…
Ultra-fast outflows (UFO) appear to be common in local active galactic nuclei (AGN) and may be powerful enough ($\dot{E}_{kin}$$\geq$1\% of L$_{bol}$) to effectively quench the star formation in their host galaxies. To test feedback models…