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arXiv · 1403.5816

The co-evolution of galaxies and supermassive black holes in the near Universe

Thaisa Storchi-Bergmann
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Abstract

A fundamental role is attributed to supermassive black holes (SMBH), and the feedback they generate, in the evolution of galaxies. But theoretical models trying to reproduce the relation between the SMBH mass and stellar velocity dispersion of the galaxy bulge make broad assumptions about the physical processes involved. These assumptions are needed due to the scarcity of observational constraints on the relevant physical processes which occur when the SMBH is being fed via mass accretion in Active Galactic Nuclei (AGN). In search for these constraints, our group -- AGN Integral Field Spectroscopy (AGNIFS) -- has been mapping the gas kinematics as well as the stellar population properties of the inner few hundred parsecs of a sample of nearby AGN hosts. In this contribution, I report results obtained so far which show gas inflows along nuclear spirals and compact disks in the inner tens to hundreds of pc in nearby AGN hosts which seem to be the sources of fuel to the AGN. As the inflow rates are much larger than the AGN accretion rate, the excess gas must be depleted via formation of new stars in the bulge. Indeed, in many cases, we find ~100 pc circumnuclear rings of recent star formation (ages ~ 10 - 500 Myr) that can be interpreted as a signature of co-evolution of the host galaxy and its AGN.

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Thaisa Storchi-Bergmann. 2014-03-23. The co-evolution of galaxies and supermassive black holes in the near Universe. https://arxiv.org/abs/1403.5816

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