scholarly journals Probing Large Scale Structures in HI with GMRT

2002 ◽  
Vol 199 ◽  
pp. 108-109 ◽  
Author(s):  
S. Bharadwaj ◽  
B.B. Nath ◽  
S.K. Sethi
Keyword(s):  
Correlation Function ◽  
Brightness Temperature ◽  
Large Scale ◽  
Background Radiation ◽  
Low Frequency ◽  
Large Scale Structure ◽  
Large Scale Structures ◽  
Point Correlation ◽  
Point Correlation Function ◽  
Scale Structures

The redshifted 1420 MHz emission from the HI in unresolved Lyman-α clouds (DLA) at high z will appear as a background radiation in low frequency radio observations. We calculate the brightness temperature and the angular two-point correlation function of the fluctuations of this radiation. This can be an important probe of the large-scale structure at high z.

FRACTAL LARGE-SCALE STRUCTURE FROM A STOCHASTIC SCALING LAW MODEL

2009 ◽  
Vol 24 (22) ◽  
pp. 1743-1748 ◽  
Author(s):  
SALVATORE CAPOZZIELLO ◽  
SCOTT FUNKHOUSER
Keyword(s):  
Correlation Function ◽  
Stochastic Model ◽  
Large Scale ◽  
Scaling Law ◽  
Mass Function ◽  
Large Scale Structures ◽  
Fractal Distribution ◽  
Point Correlation ◽  
Point Correlation Function ◽  
Scale Structures

A stochastic model relating the parameters of astrophysical structures to the parameters of their granular components is applied to the formation of hierarchical, large-scale structures from galaxies assumed as point-like objects. If the density profile of galaxies on a given scale is described by a power law, then the stochastic model leads naturally to a mass function that is proportional to the square of the distance from an occupied point, which corresponds to a two-point correlation function that is inversely proportional to the distance. This result is consistent with observations indicating that galaxies are, on the largest scales, characterized by a fractal distribution with a dimension of order 2 and well-fit with transition to homogeneity at cosmological scales.

scholarly journals The Two-Point Correlation Function of Ringed Galaxies

1996 ◽  
Vol 157 ◽  
pp. 492-494
Author(s):  
Wentao Wu ◽  
Renato A. Dupke ◽  
Carlos R. Rabaça
Keyword(s):  
Correlation Function ◽  
Large Scale ◽  
Large Scale Structures ◽  
General Field ◽  
Point Correlation ◽  
Point Correlation Function ◽  
Scale Structures

AbstractWe calculate the two-point correlation function for a sample of ringed galaxies. Results are similar to that of general field galaxies. We also find evidence that these galaxies form very large scale structures.

CHAOTIC INFLATIONARY UNIVERSE AND THE ANISOTROPY OF THE LARGE-SCALE STRUCTURE

1990 ◽  
Vol 05 (13) ◽  
pp. 2625-2646 ◽  
Author(s):  
G. V. CHIBISOV ◽  
YU. V. SHTANOV
Keyword(s):  
Correlation Function ◽  
Large Scale ◽  
Large Scale Structure ◽  
Expected Value ◽  
Scale Structure ◽  
Inflationary Universe ◽  
Point Correlation ◽  
Point Correlation Function ◽  
Inflation Scenario ◽  
Chaotic Inflation

In frames of the chaotic inflation scenario the influence of the inhomogeneity of the inflationary universe on the primordial fluctuations spectrum is investigated. The phenomenon of the anisotropy of the observed large-scale structure is predicted. In particular this means that the two-point correlation function ξ(x) is anisotropic. An expected value of the anisotropy is about 10%. The observation of the anisotropy predicted could serve as confirmation to the chaotic inflation scenario.

scholarly journals Spatial correlations of extended cosmological structures

2020 ◽  
Vol 494 (3) ◽  
pp. 3227-3234
Author(s):  
V Santucho ◽  
H E Luparello ◽  
M Lares ◽  
D G Lambas ◽  
A N Ruiz ◽  
...  
Keyword(s):  
Correlation Function ◽  
Large Scale ◽  
Relative Distribution ◽  
Spatial Correlations ◽  
Large Scale Structures ◽  
Large Structures ◽  
Point Correlation ◽  
Point Correlation Function ◽  
Cosmic Voids ◽  
The Universe

ABSTRACT Studies of large-scale structures in the Universe, such as superstructures or cosmic voids, have been widely used to characterize the properties of the cosmic web through statistical analyses. On the other hand, the two-point correlation function of large-scale tracers such as galaxies or haloes provides a reliable statistical measure. However, this function applies to the spatial distribution of point-like objects, and therefore it is not appropriate for extended large structures that strongly depart from spherical symmetry. Here we present an analysis based on the standard correlation function formalism that can be applied to extended objects exhibiting arbitrary shapes. Following this approach, we compute the probability excess Ξ of having spheres sharing parts of cosmic structures with respect to a realization corresponding to a distribution of the same structures in random positions. For this aim, we identify superstructures defined as future virialized structures (FVSs) in semi-analytic galaxies in the MPDL2 MultiDark simulation. We have also identified cosmic voids to provide a joint study of their relative distribution with respect to the superstructures. Our analysis suggests that Ξ provides useful characterizations of the large-scale distribution, as suggested from an analysis of subsets of the simulation. Even when superstructure properties may exhibit negligible variations across the subsets, Ξ has the sensitivity to statistically distinguish sub-boxes that depart from the mean at larger scales. Thus, our methods can be applied in analysis of future surveys to provide characterizations of large-scale structure suitable to distinguish different theoretical scenarios.

scholarly journals Large-Scale Structure in the Durham/Ukst Galaxy Redshift Survey

1994 ◽  
Vol 161 ◽  
pp. 693-697
Author(s):  
A. Broadbent ◽  
T. Shanks ◽  
F.G. Watson ◽  
Q.A. Parker ◽  
R. Fong ◽  
...  
Keyword(s):  
Correlation Function ◽  
Statistical Analysis ◽  
Large Scale ◽  
Large Scale Structure ◽  
Scale Structure ◽  
Point Correlation ◽  
Point Correlation Function ◽  
Redshift Survey ◽  
Galaxy Redshift ◽  
The Universe

We report on the progress of the compilation and analysis of the Durham/UKST galaxy redshift survey. This survey will probe a large contiguous volume of space within a 1500 sq. deg. area of sky around the SGP. It will contain redshifts of ∼ 4000 galaxies of bJ < 17m providing detailed information about the structure of the Universe on large scales. Large features on scales of ∼ 100h−1 Mpc are clearly visible on examination of the completed section of the survey, although a statistical analysis of the survey by means of the two-point correlation function is close to zero on scales of r > 10h−1 Mpc.

scholarly journals The effect of large-scale structure on the SDSS galaxy three-point correlation function

2006 ◽  
Vol 368 (4) ◽  
pp. 1507-1514 ◽  
Author(s):  
R. C. Nichol ◽  
R. K. Sheth ◽  
Y. Suto ◽  
A. J. Gray ◽  
I. Kayo ◽  
...  
Keyword(s):  
Correlation Function ◽  
Large Scale ◽  
Large Scale Structure ◽  
Scale Structure ◽  
Point Correlation ◽  
Point Correlation Function

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

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.

scholarly journals The Anglo-Australian Redshift Survey

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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