Structure and dynamics of the Shapley supercluster

Abstract

Abstract. We present results of our wide-field redshift survey of galaxies in a 285 square degree region of the Shapley Supercluster (SSC), based on a set of 10529 velocity measurements (including 1201 new ones) on 8632 galaxies obtained from various telescopes and from the literature. Our data reveal that the main plane of the SSC (v ≈ 14500 km s −1 ) extends further than previous estimates, filling the whole extent of our survey region of 12 degrees by 30 degrees on the skyThere is also a connecting structure associated with the slightly nearer Abell 3571 cluster complex (v ≈ 12000 km s −1 ). These galaxies seem to link two previously identified sheets of galaxies and establish a connection with a third one at v = 15000 km s −1 near R.A.= 13 h . They also tend to fill the gap of galaxies between the foreground Hydra-Centaurus region and the more distant In the velocity range of the Shapley Supercluster (9000 km s −1 < cz < 18000 km s −1 ), we found redshift-space overdensities with bj < 17.5 of ≃ 5.4 over the 225 square degree central region and ≃ 3.8 in a 192 square degree region excluding rich clusters. Over the large region of our survey, we find that the intercluster galaxies make up 48 per cent of the observed galaxies in the SSC region and, accounting for the different completeness, may contribute nearly twice as much mass as the cluster galaxies. In this paper, we discuss the completeness of the velocity catalogue, the morphology of the supercluster, the global overdensity, and some properties of the individual galaxy clusters in the Supercluster.

KEPLER OBSERVATIONS OF RAPID OPTICAL VARIABILITY IN ACTIVE GALACTIC NUCLEI

“…Table 1 gives details of the Kepler AGN whose light curves are presented in this paper, a sample of four variable AGN that Kepler has been observing since Q6. Of these four, only Zw 229−15 (z = 0.0275, Falco et al 1999, Proust 1990) had been identified as an AGN prior to the launch of Kepler. A recent reverberation mapping campaign found it had an Hβ lag Note.…”

Spectral and time series analyses of the Seyfert 1 AGN: Zw 229.015

“…Despite being relatively bright, its position in the galactic plane has E-mail : adegoke@physics.iisc.ernet.in † E-mail : suvendu.rakshit@iiap.res.in ‡ E-mail : bm@physics.iisc.ernet.in resulted in there being very little known about this source (Carini & Ryle, 2012). Its Seyfert nature was noted by Proust (1990) and it was observed in the ROSAT all sky survey by Zimmermann et al (2001). Barth et al (2011) carried out a ground based reverberation mapping campaign on the source to complement its scheduled observation with the Kepler mission.…”