Colloq Abstract - Lacy

March 8, 2019

11:00am Mountain

Mark Lacy (NRAO)

 

The impact of AGN on galaxy formation - new probes from the radio and mm

 

Abstract

Simulations of galaxy formation show that feedback by an AGN on the interstellar medium of its host galaxy is needed to prevent galaxies growing to extreme masses. The details of how AGN feedback actually works in practice is yet to be understood, however. As observers, we see interactions between the AGN and surrounding gas take several different forms, sometimes even stimulating star formation rather than preventing it. In this talk I will discuss two contrasting cases of feedback: Minkowski's Object, where a dwarf galaxy is being struck by a radio jet, and the hyperluminous quasar HE0515-4414, where we see evidence for a thermal (non-relativistic) wind via the Sunyaev-Zeldovich Effect. In both these cases, radio and/or mm-wave observations play an essential role in quantifying the effects of AGN feedback, and may help us arrive at a consistent picture of how feedback operates in practice.

 

 

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