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20.02.2019

Galaxy Evolution with present and future facilities: ALMA and SPICA

27/2/2019

Galaxy Evolution with present and future facilities: ALMA and SPICA

Dr Juan Antonio Fernández-Ontiveros

Institute for Astronomy, Astrophysics, Space Applications & Remote Sensing   

National Observatory of Athens  

 

 

An astounding fact about the Universe is that the energy released by both star formation and accretion onto supermassive black holes has decreased by a factor of 30 in the last ~7 Gyr. Feeding and feedback in Active Galactic Nuclei (AGN) are the physical mechanisms invoked to explain this behaviour and reconcile the observed galaxy masses with that of dark matter halos. While powerful outflows driven by both phenomena and more quiescent inflows are able to cause a serious impact on their host galaxies, the overall occurrence of these events among common and fainter galaxies is still to be determined. I will discuss two projects that aim to address this by characterising the typical inflow/outflow masses and the physical conditions in the wind: the ALMA Radio-source Catalog (ARC) and the Twelve micron WInd STatistics (TWIST), both based on ALMA CO observations for ~150 AGN distributed from the Local Universe up to z ~ 4. TWIST focuses on AGN where radiation pressure is important, while ARC focuses on AGN with prominent jets. So far we have detected winds in the innermost few hundred parsecs of 3 galaxies in the TWIST sample (~10%). Two of them are likely driven by the AGN jet. Because feedback also participates in the internal cycle of matter in galaxies, it plays a main role in their chemical evolution, leading to the observed mass-metallicity relation. The study of this relation is one of the main goals of the future SPace IR telescope for Cosmology and Astrophysics (SPICA), in which I participate. SPICA is a 2.5m cryogenic (< 8K) IR telescope (12-230 µm) currently in the study phase for the ESA medium-class mission call M5. I will discuss IR spectroscopic diagnostics to measure the heavy element abundance and the dust composition in galaxies at the knee of the luminosity function at each redshift. Finally, I will discuss the synergies between SPICA (planned for ~2030) and present/future first-class facilities (ALMA, ELTs, Athena, SKA).