NUMERICAL ESTIMATOR FOR LARGE-SCALE COSMIC STRUCTURES
Journal Title: Odessa Astronomical Publications - Year 2018, Vol 31, Issue
Abstract
Components of large-scale structure (LSS) of Universe includes galaxy clusters , walls , filaments , groups and field galaxies. The question of spatial organization of all these components remains open despite of a number of recently developed methods of LSS analysis. In this paper we introduce new continuous structural parameter of galaxy distribution for the determining of the type of LSS surrounding. This parameter is based on comparison of the radial distribution of galaxies around the certain point with the uniform one. Our method for structure parameter calculation is based on the distribution of 1000 closets galaxies to the selected one. Such number was selected because most galaxy clusters contains up to 1000 galaxies. When we exceed 1000th closest galaxy we will leave possible cluster or filament and will pass to another type of LSS. We suppose that in uniform distribution of galaxies their number should increase as third power a distance, similar to luminosity. Therefore the inverse dependence of galaxy distance from number should be cubic root. New structural parameter was introduced as the difference of this dependence of cubic root. The main type of cosmic surrounding for a galax is defined by the value and the sign of such structural parameter. If a galaxy lies in a cluster the distances of nearby galaxies will be less than cubic root. We integrated distance difference for all 1000 galaxies and get negative structural parameter in this case. If a galaxy lies in a void, the distances of surrounding galaxies will be larger than cubic root. In such case the structural parameter will be positive. New parameter was calculated for sky distribution of SDSS galaxies at distances from 50 to 150 Mpc. Analyzing obtained values, we come to conclusion that our structural parameter can be used for the division of LSS components and extragalactic filament detection.
Authors and Affiliations
A. V. Tugay, N. G. Pulatova, A. D. Zhoga
PERIOD VARIATIONS AND POSSIBLE THIRD COMPONENTS IN THE ECLIPSING BINARIES AH TAURI AND ZZ CASSIOPEIAE
In our research, we investigated two variable stars: AH Tau and ZZ Cas. They are eclipsing binary stars of W Ursae IMajories and Lyrae types. The period between eclipses of these stars changes with time. The reason for...
THE DAILY 110 MHZ RADIO WAVE SKY SURVEY: STATISTICAL ANALYSIS OF IMPULSE PHENOMENA FROM OBSERVATION IN 2012-2013
On the Pushchino Radio Astronomy Observatory of Lebedev Physical Institute by radio telescope BSA (Big Scanning Antenna) in 2012 started daily multi-beam observations at the frequency range 109- 112 MHz. The number of fr...
INVESTIGATION OF DIFFUSE INTERSTELLAR BANDS OF ORGANIC MOLECULES IN THE SPECTRA OF CEPHEID STARS
We describe an effective method of investigation of the Diffuse Interstellar Bands (DIBs) in the spectra of Cepheid stars. DIBs are believed to originate from the absorption of such carriers as polycyclic aromatic hydroc...
STATUS REFINEMENT OF METAL-POOR STAR HD 6268
Metal-poor stars in the Galaxy enable observations of the light and neutron-capture (n-capture) elements produced by their progenitors and deduction of the characteristics of the early Galaxy from the elemental abundance...
SOLAR CYCLES – TO UPDATING BASIC PARAMETERS
Examining daily and monthly averages of solar activity index of the northern and southern hemispheres on the total area of spots-Sp (12-24 cycles, 1874-2014), the Wolf numbers-W (22-24 cycles, 1992-2014). Application of...