Observations of Vibrationally - Excited Molecular Hydrogen in Cluster Cooling Flow Nebulae

We report the results of Hubble Space Telescope NICMOS and WFPC2 imaging of emission-line nebulae in the central galaxies of three clusters of galaxies purported to host massive cooling flows, Perseus (NGC1275), Abell 2597, and PKS0745-191. The spectral signature of vibrationally-excited molecular hydrogen has been seen in every galaxy searched thus far that is central to a cluster cooling flow with an optical emission line nebula. With the exquisite spatial resolution available to us with the Hubble Space Telescope, we have discovered that the vibrationally-excited molecular hydrogen gas extends several kpc from the centers of Abell 2597 and PKS0745-191, while the vibrationally-excited molecular hydrogen in NGC1275 appears to be mostly confined to its nucleus, with some extended emission < 1 kpc from the center. The molecular hydrogen in Abell 2597 and PKS0745-191 seems to be nearly co-spatial with the optical emission-line filaments in those systems. There may be a tiny jet visible in the 1.6 μm image of PKS0745-191. We also find significant dust absorption features in the 1.6 μm images of all three systems. The dust lanes are not strictly co-spatial with the emission-line filaments, but are aligned with and perhaps intermingled with them. The morphology of the emission-line systems suggests that the presence of vibrationally-excited