AGN feedback is widely accepted as necessary to regulate the growth of massive galaxies. However, direct evidence is scarce, and the overall impact on galaxy evolution remains controversial.
Searching for observational signatures of feedback, I have investigated the connection between AGN and star formation using a large sample of low-z AGNs, in particular, by focusing on outflows as a channel of feedback.
I will highlight the main results from a series of statistical and follow-up studies.
First, I find that strong outflow AGNs and SF galaxies have comparable star formation rate (SFR), while no-outflow AGNs show much lower SFR.
This trend suggests that there is no feedback or feedback is delayed. Second, based on IFU studies I find that ionized gas outflows are rather confined in a relatively small scale, suggesting a limited impact.
On the other hand, star formation or shock signatures are typically detected at the edge of outflows, implying that negative and positive feedback co-exists for a given object.
These results suggest no evidence of instantaneous feedback and the overall impact of outflows is rather limited.