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

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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Superclustering and Motion of Galaxy Clusters*

Symposium - International Astronomical Union ◽

10.1017/s0074180900136083 ◽

1988 ◽

Vol 130 ◽

pp. 229-238

Author(s):

Neta A. Bahcall

Keyword(s):

Dark Matter ◽

Spatial Distribution ◽

Shell Model ◽

Galaxy Clusters ◽

Large Scale ◽

Clusters Of Galaxies ◽

Large Scale Structures ◽

Peculiar Velocities ◽

Scale Structures ◽

Shell Intersections

The evidence for the existence of very large scale structures, ∼ 100h−1 Mpc in size, as derived from the spatial distribution of clusters of galaxies is summarized. A “shell model” of galaxy clustering is described in which clusters of galaxies are located at shell intersections; the model yields results consistent with cluster observations. Detection of a ∼ 2000 km s−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−1 Mpc 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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Large-Scale Structure in the Universe: Spatial Distribution and Peculiar Velocities

Observational Cosmology ◽

10.1007/978-94-009-3853-3_32 ◽

1987 ◽

pp. 335-348

Author(s):

Neta A. Bahcall

Keyword(s):

Spatial Distribution ◽

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Peculiar Velocities ◽

The Universe

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FORMATION OF LARGE SCALE STRUCTURES OF THE UNIVERSE ON THE CONNECTION MACHINE-2.

International Journal of Modern Physics C ◽

10.1142/s0129183193000203 ◽

1993 ◽

Vol 04 (01) ◽

pp. 197-205 ◽

Cited By ~ 5

Author(s):

JEAN-MICHEL ALIMI ◽

HANS SCHOLL

Keyword(s):

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Large Scale Structures ◽

Preliminary Results ◽

Connection Machine ◽

Scale Structures ◽

The Universe

We have developped two new N-body codes on Connection Machine 2. We present preliminary results concerning the formation of large scale structure of the Universe.

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Anti-symmetric clustering signals in the observed power spectrum

Journal of Cosmology and Astroparticle Physics ◽

10.1088/1475-7516/2021/12/003 ◽

2021 ◽

Vol 2021 (12) ◽

pp. 003

Author(s):

José Fonseca ◽

Chris Clarkson

Keyword(s):

Dark Matter ◽

Power Spectrum ◽

Euler Equation ◽

Large Scale ◽

Signal To Noise Ratio ◽

Power Spectra ◽

Large Scale Structure ◽

Scale Structure ◽

Signal To Noise ◽

Peculiar Velocities

Abstract In this paper, we study how to directly measure the effect of peculiar velocities in the observed angular power spectra. We do this by constructing a new anti-symmetric estimator of Large Scale Structure using different dark matter tracers. We show that the Doppler term is the major component of our estimator and we show that we can measure it with a signal-to-noise ratio up to ∼ 50 using a futuristic SKAO HI galaxy survey. We demonstrate the utility of this estimator by using it to provide constraints on the Euler equation.

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Large-Scale Structure of the Universe in Unstable Dark Matter Models

Symposium - International Astronomical Union ◽

10.1017/s0074180900136174 ◽

1988 ◽

Vol 130 ◽

pp. 293-300

Author(s):

A.G. Doroshkevich ◽

A.A. Klypin ◽

M.U. Khlopov

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Large Scale ◽

Numerical Models ◽

Large Scale Structure ◽

Scale Structure ◽

Microwave Background ◽

Physical Background ◽

The Mean ◽

The Universe

Processes of the formation and the evolution of the large-scale structure are discussed in the framework of unstable dark matter models. Six numerical models are presented. The projected distribution of simulated galaxies on the sky, wedge diagrams, correlation functions and the mean linear scale of voids are presented. Physical background of the hypothesis of unstable particles and possible observational tests are discussed. The level of the microwave background fluctuations is estimated analytically. Special attention is given to late stage of supercluster evolution and galaxy formation.

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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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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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