THE GENUS CURVE OF THE ABELL CLUSTERS

We study the topology of large-scale structure through a genus curve measurement of the recent Abell catalog redshift survey of Postman, Huchra, and Geller (1992). The structure is found to be spongelike near median density and to exhibit isolated superclusters and voids at high and low densities, respectively. The genus curve shows a slight shift toward ''meatball'' topology, but remains consistent with the hypothesis of Gaussian random phase initial conditions. The amplitude of the genus curve corresponds to a power-law spectrum with index n=0.21(-0.47)(+0.43) on scales of 48h(-1) Mpc or to a cold dark matter power spectrum with Omega h= 0.36(-0.17)(+0.46).