The line-of-sight analysis of spatial distribution of galaxies in the COSMOS2015 catalogue

Abstract

New observations of high-redshift objects are crucial for the improvement of the standard $\Lambda$CDM cosmological model and our understanding of the Universe. One of the main directions of modern observational cosmology is the analysis of the large-scale structure of Universe, in particular, in deep fields. We study the large-scale structure of the Universe along the line of sight using the latest version of the COSMOS2015 catalogue, which contains 518,404 high quality photometric redshifts of galaxies selected in the optical range of the COSMOS field ($2\times 2$ deg${}^2$), with depth up to the redshift $z\sim 6$. We analyze large-scale fluctuations in the number of galaxies along the line of sight and provide an estimate of the average linear sizes of the self-correlating fluctuations (structures) in independent redshift bins of $\Delta z=0.1$ along with the estimate of the standard deviation from homogeneity (the observed cosmic variance). We suggest a new method of the line-of-sight analysis based on previous works and formulate further prospects of method development. For the case of the theoretical form of approximation of homogeneity in the $\Lambda$CDM framework, the average standard deviation of detected structures from homogeneity is ${\sigma }_{\text{mean}}^{\Lambda \text{CDM}}=0.09\pm 0.02$, and the average characteristic size of structures is $R_{\text{mean}}^{\Lambda \text{CDM}}=790\pm 150$ Mpc. For the case of the empirical approximation of homogeneity, the average standard deviation of detected structures from homogeneity is ${\sigma }_{\text{mean}}^{\text{empiric}}=0.08\pm 0.01$, and the average characteristic size of structures is $R_{\text{mean}}^{\text{empiric}}=640\pm 140$ Mpc.

21 pages, 18 figures, Universe accepted 2020.11.19

References in corpus (14)

• COSMOS Photometric Redshifts with 30-bands for 2-deg2
• UltraVISTA: a new ultra-deep near-infrared survey in COSMOS
• COSMOS: 3D weak lensing and the growth of structure
• Cosmic Web of Galaxies in the COSMOS Field: Public Catalog and Different Quenching for Centrals and Satellites
• MultiDark-Galaxies: data release and first results
• Sloan Great Wall as a complex of superclusters with collapsing cores
• High Redshift Long Gamma-Ray Bursts Hubble Diagram as a Test of Basic Cosmological Relations
• The clustering of $z>7$ galaxies: Predictions from the BLUETIDES simulation
• Extension and estimation of correlations in Cold Dark Matter models
• Large-Scale Fluctuations in the Number Density of Galaxies in Independent Surveys of Deep Fields
• Global structure of the Local Universe according to 2MRS survey
• The Next Generation of Cosmological Measurements with Type Ia Supernovae
• Study of Faint Galaxies in the Field of GRB 021004
• THESEUS$-$BTA cosmological tests using Multimessenger Gamma-Ray Bursts observations