Gas outflowing from the AGN power source is most likely responsible of the complex interplay between the nuclear engine and the host galaxy properties, which is commonly referred to as feedback. Winds propagating at Galactic scales represent a crucial diagnostic of AGN feedback. Both numerical simulations and observations have shown that the nature of outflows in AGN is multiphase, and that...
Powerful winds driven by active galactic nuclei (AGN) are often invoked to play a fundamental role in the evolution of both supermassive black holes (SMBHs) and their host galaxies, possibly quenching star formation and explaining the tight SMBH-galaxy relations. Renewed support for this “quasar-mode” feedback came from recent X-ray observations of mildly relativistic disk winds, a.k.a....
The first ALMA observation of the nearby quasar PDS 456 (z=0.184) was designed to obtain the highest resolution map ever taken of the molecular gas in a hyper-luminous quasar. With a bolometric luminosity of 2e47 erg/s (~ Eddington luminosity) it can be regarded as the local counterpart of the quasars shining at z ~ 2, i.e. the peak of quasar luminosity density.
We are able to reveal in...
Detection of CO, HCN and H2O lines show that quasar outflows are in molecular form up to a radius of 1-10 kpc. To reach such distances, the molecular gas has to be structured in clumps, able to provide sufficient self-shielding against the strong quasar radiation field. I present numerical simulations for the structure of a molecular clumps exposed to a UV radiation field, featuring...
Galaxy formation theories struggle to explain the role of Black Hole accretion in shaping galaxies over cosmic time. Radio feedback, associated to radio jets, is accepted as a fundamental component of the lifecycle of the most massive radio loud early-type galaxies (Radio Loud ETGs, i.e. Radio Galaxies, RGs), at least in the late stages of cosmic evolution (z < 1). The many details of such...
The physical mechanism(s) driving the "quenching" of the star formation activity in galaxies, remains one of the least understood puzzles in the galaxy formation theoretical framework. According to the most recent theoretical models, the energetic feedback from active galactic nuclei (AGN) is believed to provide an effective mechanism to eject the gas away from the galaxy by powerful winds in...
Numerous models and simulations expect that AGN should have a negative feedback effect on star formation in their host galaxy, by generating outflows and by injecting energy into the ISM and in their circugalactic medium. Recent models predict that AGNs may also have a positive feedback effect by enhancing star formation in some regions of their host galaxies.
I will quickly review these...
AGN outflows are believed to play a major role in shaping the properties of host galaxies, by sweeping away the gas and quenching star formation (negative feedback).
In this framework our MAGNUM survey aims at investigating in detail the interplay between AGN activity and star formation processes in nearby active galaxies which, due to their vicinity, are the ideal laboratories to carry out...
The origin of the tight correlations observed between the masses of supermassive black
holes (SMBHs) and host galaxy properties is still debated. Negative feedback from AGN can
provide a viable explanation for these correlations. According to the theoretical models, the ejective feedback resulting from radiatively-efficient episodes of gas accretion onto SMBHs may be the main responsible for...
I will review the most important results from near-IR spectroscopic observations of WISE/SDSS selected hyper-luminous (WISSH) quasars, designed to accurately probe the role of nuclear activity in SMBH-galaxy self-regulated growth via extended outflows. The total sample consists of 90 broad-line quasars at the brightest end of the AGN luminosity function (L_bol > 1e14 L_sun) and at the peak of...
I will present evidence of AGN-driven outflows in the early Universe, resulting from the stacking analysis of a sample of 48 QSOs at z~5-7 with ALMA [CII] detection. Very broad [CII] wings are on average present, and extend beyond velocities of 1000 km/s. The luminosity associated with the broad [CII] wings correlates with the AGN luminosity, while it remains unchanged in low-high SFR sources....
