2022AstBu..77...22K

Here we present results of studying the dynamics of galaxies, properties of early-type galaxies, with the quenched star formation (QGs) in the A 2142 cluster based on the archival data from the Sloan Digital Sky Survey Data (SDSS DR10). We found the observed halo boundary, the "splashback" radius Rsp, which is equal to 4.12 Mpc (M_r < -20.^m3) and 4.06 Mpc (M_r < 21 .^m5) over the integral distribution of the number of galaxies as a function of the squared distance from the center. We have studied how early-type galaxies are distributed in the center and in the outskirts of the cluster (R/R₂₀₀ < 3, M_r < -20.^m3) and plotted the "red sequence" in the form of (g - r) = (-0.024 ± 0.001)M_r + (0.441 ± 0.005). Among all the cluster galaxies, the galaxies with the quenched star formation (-12 yr^–1 < log s SFR < 10.75 yr^–1) make up about one third. We have found that the fraction of QGs beyond the "splashback" radius R_sp s the same as in the field at the same z with coordinates of the center of 16h.5,31° and a size of 300'. For galaxies with the stellar masses log M_*/M_☉ = [10.5; 11.0] (this is the main mass range of QGs), when entering the cluster, there is a decrease in the radii R_90,r by about 30% when moving towards the center.