Seminar @ DF-AS - G. Cresci - Blowin' in the wind: feedback from QSO and AGN outflows locally and at high-z

Tipologia evento: 
Data evento
Data inizio evento: 
28/04/2016 - 11:30
Data fine evento: 
28/04/2016 - 12:30
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Quasar feedback in the form of powerful outflows is invoked as a key mechanism to quench star formation in galaxies, although direct observational evidences are still scarce, probably because radiatively driven winds are rare as they arise during a short-lived phase. I will present near-IR integral field observations of a sample of high-z QSOs, in which we clearly resolve fast (up to 1500 km/s) extended (up to 13 kpc from the black hole) outflows in the [OIII] lines, whose high velocity and high mass outflow rate are unlikely to be sustained by star formation only. Moreover, Star Formation tracers in some of these objects show that the outflow position is anti-correlated with the star forming regions in the host galaxy, representing the first direct evidences of powerful outflows removing the gas from the host galaxy (`negative feedback'). Evidences of gas depletion in these source are also provided by the direct measurement of molecular gas from PDBI and ALMA observations. However, in one of the objects we also have evidences of the opposite mechanism, star formation triggered at the edges of the outflow ('positive feedback').
Finally, I will present optical IFU observations with MUSE of a sample of nearby AGNs, the MAGNUM survey. These include NGC5643, a local Sy2 galaxies where we find evidences of outflow induced star formation in the nuclear region, further suggesting that positive feedback may be a relevant mechanism in shaping the black hole-galaxy coevolution.

Villa Bazzoni

Elena Rasia
Ultimo aggiornamento: 26-04-2016 - 10:08