Integral field spectroscopy of ionized and molecular gas in cool cluster
  cores: evidence for cold feedback?
  We present VLT-SINFONI K-band IFU spectroscopy of the central galaxies in the
cool core clusters A1664, A2204 and PKS 0745-191, to probe the Pa-alpha and
ro-vibrational H2 line emission. In A1664 the two emission-line velocity
systems seen in our previous H-alpha data appear in both Pa-alpha and H2
emission, with notable morphological differences. The recession velocity of the
red component of Pa-alpha increases linearly with decreasing radius,
particularly along an 8 kpc filament aligned with the major axis of the
underlying galaxy and the cluster X-ray emission. These kinematics are modelled
as gravitational free-fall as gas cools rapidly out of the hot phase. In A2204
the gas shows 3 or 4 filaments reaching 10 kpc, three of which lie towards
`ghost bubbles' seen in X-ray imaging. For PKS 0745-191, we confirm the
twin-arm morphology of previous narrow-band images; the Pa-alpha kinematics
suggest rotational motion about an axis aligned with the kpc-scale radio jet;
on nucleus, we find a broad Pa-alpha component (FWHM 1700 km/s) and a secondary
H2 system redshifted by +500 km/s.
  The H2 v=1-0 S(3)/Pa-alpha ratio is highest in isolated and extended regions
where it matches the levels in the NGC 1275 filaments as modelled by Ferland et
al. Regions with lower ratios highlight active star formation and are often
kinematically quiescent (FWHM < 200 km/s). Our findings suggest that these
clusters may be captured in different stages of the `cold feedback' cycle of
Pizzolato & Soker, with A1664 in a brief phase of extreme cooling and star
formation prior to an AGN heating event; PKS 0745-191 in outburst with the AGN
accreting from a cool gas disk, and A2204 in a later phase where cool gas is
dragged out of the galaxy by the buoyant rise of old radio bubbles (abridged).
