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Information × Registration Number 0225U001765, (0120U100162) , R & D reports Title Dynamic and chemical evolution of galaxies and galactic structures popup.stage_title Динамічна і хімічна еволюція галактик та галактичних структур Head Bertsyk Peter P., Доктор фізико-математичних наук Registration Date 06-02-2025 Organization Main Astronomical Observatory of the National Academy of Sciences of Ukraine popup.description1 The purposes of the project are 1) to conduct a versatile stellar-dynamic study of scattered stellar clusters from the moment of their formation to the collapse; 2) to study the dynamic merging of supermassive black holes in galactic nuclei undergoing the merging phase and to obtain frequency-time and amplitude-frequency pictures of merging for supermassive black holes to sample interacting galaxies at different redshifts; 3) to construct of maps of distribution of parameters (brightness surfaces, rotation velocities, extinction, star formation and oxygen and nitrogen abundances) in several hundred galaxies and determination of fundamental parameters of galaxies (rotation speed, metallicity in the center of the galaxy, radial gradient) on the base of constructed maps; 4) to find out the dependence of the chemical composition of the galaxy on its global parameters. popup.description2 The results of modeling the dynamical evolution of double and triple systems of supermassive black holes, the formation of black holes in merging star clusters and galaxies, and the co-evolution of black holes and star clusters are presented. The physical time of the merger of the double supermassive black hole system in the center of the interacting galaxy NGC 6240 is estimated. We study the counter-rotation in the torus obscuring NGC 1068 and show that it is explained by the influence of the asymmetric wind, which we consider as a radiation pressure, and the effects of the torus orientation. The orbital parameters of bound and unbound stars undergoing tidal destruction are investigated by comparing the data of direct N-body modeling with the analytical model. An analytical model of the formation and evolution of stellar clusters is constructed and the orbits of 147 globular clusters (GCs) are simulated over a 10 billion-year interval using the parallel N-body code φ-GPU. We present the results of a search for galaxies in the local Universe with extremely low oxygen abundance, more than 25 times lower than the solar one. A subset of galaxies with a redshift less than 0.5 from the DESI EDR survey (DESI Collaboration 2023) is analyzed to detect galaxies with ultra-low metal abundance. The galaxy J0713+5608 was found to have the lowest oxygen abundance of all known galaxies - 6.978± 0.095 dex. The oxygen abundance (O/H), nitrogen-to-oxygen ratio (N/O), and their radial gradients were obtained for a sample of 1431 galaxies from the MaNGA DR15 survey. We also obtained the oxygen abundance in the gas phase for 69 galaxies from the MaNGA DR17 survey. The search for galaxies similar to our Galaxy among the sample of about 500 galaxies is carried out. Four galaxies (NGC 3521, NGC 4651, NGC 2903 and MaNGA galaxy M-8341-09101) are found that can be considered as twins of the Milky Way. Also, signs indicating that the evolution of our Galaxy is not typical are found. Product Description popup.authors Ishchenko Maryna V. Vovk Kateryna B. Zinchenko Ihor A. Masliukh Volodymyr O. Mykhailytska Nina H. Nykytiuk Tetiana V. Piliuhin Leonid S. Sobolenko Marharyta O. popup.nrat_date 2025-02-06 Close