Related papers: Dynamical complexity in micro-scale disk-wind syst…
We use a disk galaxy evolution model to investigate the impact of mass outflows (a.k.a. feedback) on disk galaxy scaling relations. Our model follows the accretion, cooling, star formation and ejection of baryonic mass inside growing dark…
Understanding the physics and geometry of accretion and ejection around super massive black holes (SMBHs) is important to understand the evolution of active galactic nuclei (AGN) and therefore of the large scale structures of the Universe.…
Tidal disruption events (TDEs) can potentially probe low-mass black holes in host galaxies that might not adhere to bulge or stellar-dispersion relationships. At least initially, TDEs can also reveal super-Eddington accretion. X-ray…
Active Galactic Nuclei (AGN) represent the growth phases of the supermassive black holes in the center of almost every galaxy. Powerful, highly ionized winds, with velocities $\sim 0.1- 0.2c$ are a common feature in X--ray spectra of…
In Tombesi et al. (2015), we reported the first direct evidence for a quasar accretion disk wind driving a massive molecular outflow. The target was F11119+3257, an ultraluminous infrared galaxy (ULIRG) with unambiguous type-1 quasar…
Observations of accreting systems often show significant variability (10-20 percent of accretion luminosity) on timescales much longer than expected for the disc regions releasing most of the luminosity. We propose an explicit physical…
Recent X-ray observations of blue-shifted absorption lines revealed an existence of the extremely fast disk winds with outflow velocities of ~0.1-0.3c. Such fast outflows would have a large impact on the coevolution of black holes and host…
I show that Eddington accretion episodes in AGN are likely to produce winds with velocities $v \sim 0.1c$ and ionization parameters up to $\xi \sim 10^4$ (cgs), implying the presence of resonance lines of helium-- and hydrogenlike iron.…
The deposition of mechanical feedback from a supermassive black hole (SMBH) in an active galactic nucleus (AGN) into the surrounding galaxy occurs via broad-line winds which must carry mass and radial momentum as well as energy. The effect…
(Abridged) We measure and analyze the energy, momentum, and mass feedback efficiencies due to radiation from AGN in relatively large scale outflows. Our measurements are based on the axisymmetric and time-dependent radiation-hydrodynamical…
We study outflows driven by Active Galactic Nuclei (AGNs) using high- resolution simulations of idealized z=2 isolated disk galaxies. Episodic accretion events lead to outflows with velocities >1000 km/s and mass outflow rates up to the…
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…
Using long-duration general relativistic magnetohydrodynamic simulations of radiatively inefficient accretion discs, the energy, momentum and mass outflow rates from such systems are estimated. Outflows occur via two fairly distinct modes:…
The actual mechanism(s) powering galactic outflows in active galactic nuclei (AGN) is still a matter of debate. At least two physical models have been considered in the literature: wind shocks and radiation pressure on dust. Here we provide…
I review accretion and outflow in active galactic nuclei. Accretion appears to occur in a series of very small--scale, chaotic events, whose gas flows have no correlation with the large--scale structure of the galaxy or with each other. The…
We predict the evolution of giant clumps undergoing star-driven outflows in high-z gravitationally unstable disk galaxies. We find that the mass loss is expected to occur through a steady wind over many tens of free-fall times (t_ff ~ 10…
Among a number of active galactic nuclei (AGNs) that drive ionized outflows in X-rays, a low-redshift (z = 0.184) quasar, PDS 456, is long known to exhibit one of the exemplary ultra-fast outflows (UFOs). However, the physical process of…
X-ray evidence for ultra-fast outflows (UFOs) has been recently reported in a number of local AGNs through the detection of blue-shifted Fe XXV/XXVI absorption lines. We present the results of a comprehensive spectral analysis of a large…
Ultra-fast outflows (UFOs) play a key role in the AGN feedback mechanism. It is therefore important to fully characterize their location and energetics. We study the UFO in the latest XMM-Newton archival observation of the NLSy1 galaxy PG…
We explore the poloidal structure of two-dimensional (2D) MHD winds in relation to their potential association with the X-ray warm absorbers (WAs) and the highly-ionized ultra-fast outflows (UFOs) in AGN, in a single unifying approach. We…