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Information × Registration Number 0226U003431, (0125U002943) , R & D reports Title Active processes in isolated galaxies in the local Universe popup.stage_title Класифікація за типом активності ізольованих галактик ближнього Всесвіту та апертурна фотометрія обраних ізольованих галактик за даними космічних та наземних телескопів Head Kompaniiets Olena V., молодший науковий співробітник Registration Date 06-04-2026 Organization Main Astronomical Observatory of the National Academy of Sciences of Ukraine popup.description1 To obtain new data on the physical properties and active processes in isolated galaxies in the local Universe (z < 0.05) and to analyze the influence of their environment on these processes. To achieve this goal, we will use multi-wavelength aperture photometry, numerical modeling of the spectral energy distributions (SED) of galaxies using the CIGALE software. popup.description2 At the first stage of the project, a systematic analysis was carried out for a sample of isolated galaxies from the 2MIG catalog with available SDSS spectroscopic data. Using the BPT diagram, 147 isolated galaxies were classified by activity type. The resulting distribution by class is as follows: 48 star-forming galaxies, 41 composite systems, 45 LINERs, 12 Seyfert galaxies, and 2 unclassified objects. For each galaxy, estimates of the local environmental density obtained within the previous project were used, based on 2D and 3D Voronoi tessellation as well as the k-nearest neighbors method. For nearby objects ($z < 0.02$), the projected surface density $\Sigma^{2D}{\rm Vor}$ was applied, while for galaxies at higher redshifts ($z \geq 0.02$), either the three-dimensional density $\Sigma^{3D}{\rm Vor}$ or the simplified estimate $\Sigma_{\rm simple}$ was used. Comparing these characteristics with the BPT classes by means of the Kruskal–Wallis test revealed no statistically significant differences in the distributions of local density among star-forming, composite, LINER, and Seyfert galaxies. This indicates a weak or absent influence of local environmental density on the nuclear activity type in isolated barred galaxies, and is also consistent with numerical models according to which bar formation is governed primarily by internal processes rather than by the environment. A custom Python pipeline was developed and tested for aperture photometry of isolated galaxies using GALEX ultraviolet survey data in the FUV and NUV bands. For each object, image cutouts were produced, binary masks were created to remove foreground sources and line-of-sight companions, background emission was estimated and subtracted using Background2D, and Milky Way interstellar extinction was taken into account based on the IRSA Dust Extinction Service. This toolkit formed the basis for the subsequent multi-wavelength SED analysis of isolated galaxies at the next stage of the project. Product Description popup.authors Olena V. Kompaniiets Inna O. Izviekova Olena S. Pastoven popup.nrat_date 2026-04-06 Close