The detailed nature of active central cluster galaxies
  We present detailed integral field unit (IFU) observations of the central few
kiloparsecs of the ionised nebulae surrounding four active central cluster
galaxies (CCGs) in cooling flow clusters (Abell 0496, 0780, 1644 and 2052). Our
sample consists of CCGs with H{\alpha} filaments, and have existing data from
the X-ray regime available. Here, we present the detailed optical emission-line
(and simultaneous absorption line) data over a broad wavelength range to probe
the dominant ionisation processes, excitation sources, morphology and
kinematics of the hot gas (as well as the morphology and kinematics of the
stars). This, combined with the other multiwavelength data, will form a
complete view of the different phases (hot and cold gas and stars) and how they
interact in the processes of star formation and feedback detected in central
galaxies in cooling flow clusters, as well as the influence of the host
cluster. We derive the optical dust extinction maps of the four nebulae. We
also derive a range of different kinematic properties, given the small sample
size. For Abell 0496 and 0780, we find that the stars and gas are kinematically
decoupled, and in the case of Abell 1644 we find that these components are
aligned. For Abell 2052, we find that the gaseous components show rotation even
though no rotation is apparent in the stellar components. To the degree that
our spatial resolution reveals, it appears that all the optical forbidden and
hydrogen recombination lines originate in the same gas for all the galaxies.
Based on optical diagnostic ratios ([OIII]{\lambda}5007/H{\beta} against
[NII]{\lambda}6584/H{\alpha}, [SII]{\lambda}{\lambda}6717,6731/H{\alpha}, and
[OI]{\lambda}6300/H{\alpha}), all galaxies show extended LINER emission, but
that at least one has significant Seyfert emission areas, and at least one
other has significant HII like emission line ratios for many pixels. ABRIDGED.
