A Near-Infrared look at AGN Feedback in Bulgeless Galaxies
  While it is generally believed that supermassive black holes (SMBH) lie in
most galaxies with bulges, few SMBHs have been confirmed in bulgeless galaxies.
Identifying such a population could provide important insights to the BH seed
population and secular BH growth. To this end, we obtained near-infrared
spectroscopic observations of a sample of low-redshift bulgeless galaxies with
mid-infrared colors suggestive of AGN. We find additional evidence of AGN
activity (such as coronal lines and broad permitted lines) in 69$\%$ (9/13) of
the sample, demonstrating that mid-infrared selection is a powerful tool to
detect AGN. More than half of the galaxies with confirmed AGN activity show
fast outflows in [O III] in the optical and/or [Si VI] in the NIR, with the
latter generally having much faster velocities that are also correlated to
their spatial extent. We are also able to obtain virial BH masses for some
targets and find they fall within the scatter of other late-type galaxies in
the $M_{\rm{BH}}$-$M_{\rm{stellar}}$ relation. The fact that they lack a
significant bulge component indicates that secular processes, likely
independent of major mergers, grew these BHs to supermassive sizes. Finally, we
analyze the rotational gas kinematics and find two notable exceptions: two AGN
hosts with outflows that appear to be rotating faster than expected. There is
an indication that these two galaxies have stellar masses significantly lower
than expected from their dark matter halo masses. This, combined with the
observed AGN activity and strong gas outflows may be evidence of the effects of
AGN feedback.
