The Pisces-Cetus supercluster (redshift z similar to 0.06) is one of the richest nearby (z <0.1) superclusters of galaxies, and emerges as a remarkable filament of galaxies at the edges of the two-degree Field Galaxy Redshift Survey (2dFGRS) and the ongoing Sloan Digital Sky Survey (SDSS). We explore the extent of the supercluster on the sky and in redshift space, and map the distribution of its constituent clusters and groups. We find evidence of enhanced star formation in galaxies belonging to groups in the supercluster compared to those in the field. This effect appears to be higher among the poorer groups than in the richer ones. In contrast, star formation is suppressed in the galaxies in rich clusters, which is consistent with previous studies. We identify two major filaments in this supercluster, consisting of 11 and 5 Abell clusters, including Abell 133 and Abell 85, respectively, and estimate the virial masses of the clusters from their velocity dispersions and optical surface brightness profiles. The lower limit to the masses of these filaments, amounting to the total virial mass of the constituent clusters, turns out to be 5.2 x 10(15) h(70)(-1) M circle dot and 6.0 x 10(15) h(70)(-1) M-circle dot over volumes of almost 6750 h(70)(-3) Mpc(3) and 19600 h(70)(-3) Mpc(3), respectively. This corresponds to mass overdensities of Omega/Omega(crit) equivalent to delta(M) > 4.7 and delta(M) > 1.3 for the two filaments making up the supercluster.
- cosmology : large-scale structure of the Universe
- X-rays : galaxies : clusters
- galaxies : clusters : general
- galaxies : evolution