The Perseus Supercluster

In analyzing the distribution of galaxies of a sample projected on the plane of the sky, the magnitude of a surface density enhancement produced by a clumpy structure depends on the size and magnitude of the volume density enhancement, and the depth of the sample. If the sample is too deep, or the line of sight size or volume overdensity of the clump too small, the surface enhancement may be too shallow to discern against the fore- and background objects. The Catalogue of Galaxies and Clusters of Galaxies (CGCG: Zwicky et al. 1960–68) provides a representative sample of the local universe (cz ≤ 15000 km s−1) and, in hindsight, possibly the one available that best enhances the inhomogeneities that appear to characterize the large scale structure of the universe. Using maps of the surface density distribution of galaxies from the CGCG, of which figure 1 is an example, Martha Haynes, Guido Chincarini and I have selected a number of filamentary structures discernable and undertaken a 21 cm redshift survey of large regions enclosing them, with the telescopes of 305 m at Arecibo and 92 m at NRAO-Green Bank. Here I shall discuss our current results from a large area extending from Pegasus to Ursa Major, which engulfs the well known Perseus supercluster (Einasto et al. 1980; Gregory et al. 1981).

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The Las Campanas/AAT Rich Cluster Survey

Publications of the Astronomical Society of Australia ◽

10.1071/as98273 ◽

1998 ◽

Vol 15 (3) ◽

pp. 273-279 ◽

Cited By ~ 6

Author(s):

Eileen O'Hely ◽

Warrick J. Couch ◽

Ian Smail ◽

Alastair C. Edge ◽

Ann Zabludoff

Keyword(s):

Galaxy Evolution ◽

Large Scale ◽

High Redshift ◽

Clusters Of Galaxies ◽

Local Universe ◽

Rich Cluster ◽

Continuous Coverage ◽

Galaxy Populations ◽

First Time ◽

The Universe

AbstractSome unsolved cosmological questions remain in relation to the formation of structure in the universe. One way of addressing such questions is to use rich galaxy clusters as tracers of the growth of large-scale structure. To date, studies of rich clusters of galaxies have concentrated on systems generally at either high redshift or in the local universe. The properties of clusters and their constituent galaxies at these extrema are becoming well understood. In particular, it is becoming clear that rich clusters have undergone considerable evolution both dynamically and in their galaxy populations over the last 5–8 Gyr. We are undertaking a detailed study of rich clusters of galaxies in the range 0·05 ≲ z ≲ 0·15. Our results will be directly comparable to those of previous studies both at high and low redshift and, for the first time, provide continuous coverage across this important and unexplored transitory epoch in terms of galaxy evolution and structure growth.

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Large-Scale Flows in the Local Universe

Symposium - International Astronomical Union ◽

10.1017/s0074180900110058 ◽

1996 ◽

Vol 168 ◽

pp. 175-182 ◽

Cited By ~ 1

Author(s):

D.S. Mathewson ◽

V.L. Ford

Keyword(s):

Large Scale ◽

Velocity Measurements ◽

Local Universe ◽

Peculiar Velocities ◽

Redshift Surveys ◽

Density Maps ◽

The Universe ◽

Great Wall ◽

Great Attractor ◽

Streaming Flow

Peculiar velocity measurements of 2500 southern spiral galaxies show large-scale flows in the direction of the Hydra-Centaurus clusters which fully participate in the flow themselves. The flow is not uniform over this region and seems to be associated with the denser regions which participate in the flow of amplitude about 400km/s. In the less dense regions the flow is small or non-existent. This makes the flow quite asymmetric and inconsistent with that expected from large-scale, parallel streaming flow that includes all galaxies out to 6000km/s as previously thought. The flow cannot be modelled by a Great Attractor at 4300km/s or the Centaurus clusters at 3500km/s. Indeed, from the density maps derived from the redshift surveys of “optical” and IRAS galaxies, it is difficult to see how the mass concentrations can be responsible particularly as they themselves participate in the flow. These results bring into question the generally accepted reason for the peculiar velocities of galaxies that they arise solely as a consequence of infall into the dense regions of the universe. To the N. of the Great Attractor region, the flow increases and shows no sign of diminishing out to the redshift limit of 8000km/s in this direction. We may have detected flow in the nearest section of the Great Wall.

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Large-Scale Structure in the Universe: Spatial Distribution and Peculiar Velocities

Symposium - International Astronomical Union ◽

10.1017/s0074180900159303 ◽

1987 ◽

Vol 124 ◽

pp. 335-348

Author(s):

Neta A. Bahcall

Keyword(s):

Dark Matter ◽

Spatial Distribution ◽

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Clusters Of Galaxies ◽

Large Scale Structures ◽

Peculiar Velocities ◽

Scale Structures ◽

The Universe

The evidence for the existence of very large scale structures, ∼ 100h−1Mpc in size, as derived from the spatial distribution of clusters of galaxies is summarized. Detection of a ∼ 2000 kms−1 elongation in the redshift direction in the distribution of the clusters is also described. Possible causes of the effect are peculiar velocities of clusters on scales of 10–100h−1Mpc and geometrical elongation of superclusters. If the effect is entirely due to the peculiar velocities of clusters, then superclusters have masses of order 1016.5M⊙ and may contain a larger amount of dark matter than previously anticipated.

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The AAO 2DF QSO Redshift Survey

Symposium - International Astronomical Union ◽

10.1017/s0074180900132504 ◽

1999 ◽

Vol 183 ◽

pp. 178-184 ◽

Cited By ~ 4

Author(s):

B.J. Boyle ◽

R.J. Smith ◽

T. Shanks ◽

S.M. Croom ◽

L. Miller

Keyword(s):

Large Scale ◽

Cosmological Parameters ◽

Large Scale Structure ◽

Scale Structure ◽

Redshift Survey ◽

The Universe

The study of large-scale structure through QSO clustering provides a potentially powerful route to determining the fundamental cosmological parameters of the Universe (see Croom & Shanks 1996). Unfortunately, previous QSO clustering studies have been limited by the relatively small sizes of homogeneous QSO catalogues that have been available. Although approximately 10,000 QSOs are now known (Veron-Cetty & Veron 1997), the largest catalogues suitable for clustering studies contain only 500–1000 QSOs (Boyle et al. 1990, Crampton et al. 1990, Hewett et al. 1994). Even combining all such suitable catalogues, the total number of QSOs which can be used for clustering studies is still only about 2000.

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Formation Times for Rich Clusters of Galaxies

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000015113 ◽

1977 ◽

Vol 3 (2) ◽

pp. 140-142 ◽

Cited By ~ 1

Author(s):

B. M. Lewis

Keyword(s):

Gaussian Distribution ◽

Large Scale ◽

Velocity Dispersion ◽

Large Scale Structure ◽

Elliptical Galaxies ◽

Scale Structure ◽

Clusters Of Galaxies ◽

Number Density ◽

Radial Gradient ◽

The Universe

Rich clusters of galaxies are a common feature of the large-scale structure of the Universe. Those studied so far, show striking regularities with (a)a smooth radial gradient of number density.(b)’isothermal’ distributions, which according to Bahcall (1975) have a scatter of only ±15% in the size of their characteristic core radii.(c)their limiting structural diameters are ~50 Mpc (cf. Abell, 1975), if they are identified with superclusters.(d)the magnitude of the velocity dispersion about their centres is generally 600-1000 km s-1, and the velocities are cpnsistent with a gaussian distribution (Yahil and Vidal, 1976; also Faber and Dressier, 1976).(e)The extreme velocities are generally within ±3000 km s-1, and for Coma are ∼2400 km s-1 (Tifft and Gregory, 1976).(f)elliptical galaxies tend to predominate near the centre, spirals in the surrounding loose groups.

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The Anglo-Australian Redshift Survey

Symposium - International Astronomical Union ◽

10.1017/s0074180900038894 ◽

1983 ◽

Vol 104 ◽

pp. 175-175

Author(s):

J. Bean ◽

G. Efstathiou ◽

R. S. Ellis ◽

B. A. Peterson ◽

T. Shanks ◽

...

Keyword(s):

Correlation Function ◽

Luminosity Function ◽

Large Scale ◽

Peculiar Velocities ◽

Point Correlation ◽

Point Correlation Function ◽

Redshift Survey ◽

Density Inhomogeneities ◽

The Universe

The aim of the survey is to sample a relatively large, randomly chosen volume of the Universe in order to study the large-scale distribution of galaxies using the two-point correlation function, the peculiar velocities between galaxy pairs and to provide an estimate of the galaxian luminosity function that is unaffected by density inhomogeneities and Virgo infall.

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Clusters of Galaxies

Highlights of Astronomy ◽

10.1017/s1539299600004627 ◽

1980 ◽

Vol 5 ◽

pp. 699-714 ◽

Cited By ~ 1

Author(s):

Neta A. Bahcall

Keyword(s):

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Clusters Of Galaxies ◽

Groups Of Galaxies ◽

Formation And Evolution ◽

The Rich ◽

The Many ◽

The Universe

AbstractClusters and groups of galaxies contain the majority of galaxies in the universe. The rich clusters, while less numerous than the many poor groups, are the densest and largest systems known, and can be easily recognized and studied even at relatively large distances. Their study is important for understanding the formation and evolution of clusters and galaxies, and for a determination of the large-scale structure in the universe.

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