Molecular Gas Heating and Modified Dust Properties in Active Galaxies:
  Growing Black Holes or Tidal Shocks?
  We investigate if and how growing super-massive black holes (SMBH) known as
Active Galactic Nuclei (AGN) and gravitational interactions affect the warm
molecular gas and dust of galaxies. Our analysis focuses on the morphologies
and warm ISM properties of 630 galaxies at z < 0.1. We use grizy images from
the Pan-STARRS survey to classify the galaxies into mergers, early mergers, and
non-mergers. We use MIR spectroscopic measurements of emission from rotational
H2 transitions, dust and PAH features, and silicate emission or absorption
lines at 9.7 microns to study how gravitational interactions impact the warm
ISM in AGN and non-AGN hosts. We find that in AGN-hosts, the ISM is warmer, the
ratios of H2 to PAHs are larger, the PAH emission line ratios and silicate
strengths have a wider range of values than in non-AGN hosts. We find some
statistical differences between the H2 emission of mergers and non-mergers, but
those differences are less statistically significant than those between AGN and
non-AGN hosts.
