SUPERCLUSTERING AT HIGH REDSHIFTS

Evidence is presented which suggests that the radio emission from distant quasars and radio galaxies is not randomly directed, but rather has preferred orientations with respect to surrounding large-scale structures. Specifically, the radio major axes of high-redshift sources exhibit a significant tendency to point in the direction of neighboring quasars and radio galaxies, for separations up to approximately 45h-1 Mpc (comoving). This alignment phenomenon is very similar to that seen at low redshifts between neighboring rich clusters and their brightest member galaxies, which suggests that what is being seen here is tentative evidence of the existence of a filamentary pattern of superclustering at redshifts z approximately 1 or more. If the alignment effect found here is confirmed with larger and more homogeneous samples, then the orientations of extragalactic radio sources may provide a very useful probe of large-scale structure at high redshifts. These results may also help shed some light on the recently discovered tendency for the extended radio and optical emissions from high redshift radio sources to be aligned.