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Title: Redshift distortions of galaxy correlation functions

Abstract

To examine how peculiar velocities can affect the 2-, 3-, and 4-point correlation functions, we evaluate volume-average correlations for configurations that emphasize and minimize distortions for four different volume-limited samples from each of the CfA, SSRS, and IRAS redshift catalogs. We present the results as the correlation length r{sub 0} and power index {gamma} of the 2-point correlation, {anti {Xi}}{sub 2} = (r{sub 0}/r){sup {gamma}}, and as the hierarchical amplitudes of the 3- and 4-point functions, S{sub 3} = {anti {Xi}}{sub 3}/{anti {Xi}}{sub 2}{sup 2} and S{sub 4} = {anti {Xi}}/{anti {Xi}}{sub 2}{sup 3}. We find a characteristic distortion for {anti {Xi}}{sub 2}: The slope {gamma} is flatter and the correlation length is larger in redshift space than in real space; that is, redshift distortions ``move`` correlations from small to large scales. At the largest scales, extra power in the redshift distribution is compatible with {Omega}{sup 4/7}/b {approx} 1; we find 0.53 {plus_minus} 0.15, 1.10 {plus_minus} 0.16 and 0.84 {plus_minus} 0.45 for the CfA, SSRS and IRAS catalogs. Higher order correlations {anti {Xi}}{sub 3} and {anti {Xi}}{sub 4} suffer similar redshift distortions, but in such a way that, within the accuracy of our analysis, the normalized amplitudes S{sub 3} andmore » S{sub 4} are insensitive to this effect. The hierarchical amplitudes S{sub 3} and S{sub 4} are constant as a function of scale between 1-12 h{sup {minus}1} Mpc and have similar values in all samples and catalogues, S{sub 3} {approx} 2 and S{sub 4} {approx} 6, despite the fact that {anti {Xi}}{sub 2}, {anti {Xi}}{sub 3}, and {anti {Xi}}{sub 4} differ from one sample to another by large factors. The agreement between the independent estimations of S{sub 3} and S{sub 4} is remarkable given the different criteria in the selection of galaxies and also the difference in the resulting range of densities, luminosities and locations between samples.« less

Authors:
 [1];  [1]
  1. Fermi National Accelerator Lab., Batavia, IL (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States); National Aeronautics and Space Administration, Washington, DC (United States)
OSTI Identifier:
10160622
Report Number(s):
FNAL/Pub-93-097-A
ON: DE93014007; CNN: Grant NAGW-2381
DOE Contract Number:  
AC02-76CH03000
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 12 May 1993
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GALAXY CLUSTERS; CORRELATION FUNCTIONS; FREQUENCY DEPENDENCE; 661300; OTHER ASPECTS OF PHYSICAL SCIENCE

Citation Formats

Fry, J N, Florida Univ., Gainesville, FL, Gaztanaga, E, and Oxford Univ. Redshift distortions of galaxy correlation functions. United States: N. p., 1993. Web. doi:10.2172/10160622.
Fry, J N, Florida Univ., Gainesville, FL, Gaztanaga, E, & Oxford Univ. Redshift distortions of galaxy correlation functions. United States. https://doi.org/10.2172/10160622
Fry, J N, Florida Univ., Gainesville, FL, Gaztanaga, E, and Oxford Univ. 1993. "Redshift distortions of galaxy correlation functions". United States. https://doi.org/10.2172/10160622. https://www.osti.gov/servlets/purl/10160622.
@article{osti_10160622,
title = {Redshift distortions of galaxy correlation functions},
author = {Fry, J N and Florida Univ., Gainesville, FL and Gaztanaga, E and Oxford Univ.},
abstractNote = {To examine how peculiar velocities can affect the 2-, 3-, and 4-point correlation functions, we evaluate volume-average correlations for configurations that emphasize and minimize distortions for four different volume-limited samples from each of the CfA, SSRS, and IRAS redshift catalogs. We present the results as the correlation length r{sub 0} and power index {gamma} of the 2-point correlation, {anti {Xi}}{sub 2} = (r{sub 0}/r){sup {gamma}}, and as the hierarchical amplitudes of the 3- and 4-point functions, S{sub 3} = {anti {Xi}}{sub 3}/{anti {Xi}}{sub 2}{sup 2} and S{sub 4} = {anti {Xi}}/{anti {Xi}}{sub 2}{sup 3}. We find a characteristic distortion for {anti {Xi}}{sub 2}: The slope {gamma} is flatter and the correlation length is larger in redshift space than in real space; that is, redshift distortions ``move`` correlations from small to large scales. At the largest scales, extra power in the redshift distribution is compatible with {Omega}{sup 4/7}/b {approx} 1; we find 0.53 {plus_minus} 0.15, 1.10 {plus_minus} 0.16 and 0.84 {plus_minus} 0.45 for the CfA, SSRS and IRAS catalogs. Higher order correlations {anti {Xi}}{sub 3} and {anti {Xi}}{sub 4} suffer similar redshift distortions, but in such a way that, within the accuracy of our analysis, the normalized amplitudes S{sub 3} and S{sub 4} are insensitive to this effect. The hierarchical amplitudes S{sub 3} and S{sub 4} are constant as a function of scale between 1-12 h{sup {minus}1} Mpc and have similar values in all samples and catalogues, S{sub 3} {approx} 2 and S{sub 4} {approx} 6, despite the fact that {anti {Xi}}{sub 2}, {anti {Xi}}{sub 3}, and {anti {Xi}}{sub 4} differ from one sample to another by large factors. The agreement between the independent estimations of S{sub 3} and S{sub 4} is remarkable given the different criteria in the selection of galaxies and also the difference in the resulting range of densities, luminosities and locations between samples.},
doi = {10.2172/10160622},
url = {https://www.osti.gov/biblio/10160622}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed May 12 00:00:00 EDT 1993},
month = {Wed May 12 00:00:00 EDT 1993}
}