Two-dimensional spectrophotometry of the cores of X-ray luminous clusters

The results of a two-dimensional spectrophotometric survey of the core regions of 11 rich clusters of galaxies are presented. A number of these clusters have spectacular optical emission line systems in their cores. Both morphologically and kinematically, the emission line regions divide into extended, 20-100 kpc systems of long linear filaments associated with the cluster core and more compact, homogeneous elongated regions associated with the dominant central cluster galaxy. It is suggested that the present results can be expected, as hot X-ray emitting gas cools in the cluster center. Luminosities almost entirely agree with expected values. The morphology of the systems can be understood if the filaments form initially in the cooling flow and, in some cases, are subsequently accreted by the central galaxy.