GALAXY AND CLUSTER REDSHIFT OBSERVATIONS IN THE SEXTANS-LEO REGION

As part of a continuing program of redshift observations for mapping large-scale structure in the universe, we present results for fourteen North Galactic Cap Abell clusters that were previously unmeasured, another ten Abell clusters in which only one or two cluster galaxies had been observed, and six poor Zwicky clusters. Most of the observed clusters are in the general direction of a supercluster candidate in Sextans-Leo {Batuski & Burns [AJ, 90, 1413 (1985a)]}, and the new cluster position data indicate that the candidate is not a single, rather densely connected supercluster. Instead, it could be three separate superclusters, one of which appears to be a substantially extended version of the Coma/A1367 supercluster of Gregory & Thompson [ApJ, 222, 784 (1978)]. The three apparent superclusters surround a void of clusters with minimum dimensions 80 x 80 x 150(h-1 Mpc)3 (h = H0/100 Mpc km-1 s-1). Five of the observed clusters are in other portions of the northern cap, and their new positions better define the emptiness of the Bootes void and the void of Bahcall & Soneira [ApJ, 262, 419 (1982)]. We also present results of some observations of individual galaxies that appear in projection to be well within the void outlined by clusters in Sextans-Leo. These redshifts were obtained with the multiple-aperture MX Spectrometer at Steward Observatory.