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Information × Registration Number 0225U001598, (0122U001834) , R & D reports Title Modeling the luminosity of elements of the large-scale structure of the early universe and the remnants of galactic supernovae, the observation of variable stars popup.stage_title Моделювання свічення елементів великомасштабної структури раннього всесвіту і залишків галактичних наднових та спостереження змінних зір Head Novosiadlyi Bohdan S., Доктор фізико-математичних наук Registration Date 03-02-2025 Organization Ivan Franko National University of Lviv popup.description1 Investigation of the formation of haloes and large voids in the epochs of Dark Ages and Cosmic Dawn and their overluminosities against the background of cosmic microwave relic radiation or absorption signals in the transition lines between the lowest rotational levels of the first molecules and the two levels of the hyperfine structure of the ground state of atomic hydrogen in cosmological models with different types of hidden components and presence of the primordial magnetic field. To develop new sensitive tests on the nature of hidden components and models of early inflation by applying the methods of complex network analysis and machine learning to study the topology and evolution of the large-scale structure of the Universe (Cosmic Web). Generalization of methods for synthesis of radio polarization maps of supernova remnants in cases of inhomogeneous medium for analysis of observational data. popup.description2  The formation of the line of the hyperfine structure of the 21 cm hydrogen atom in the cosmological epochs of the Dark Ages (20<z<200), the Cosmic Dawn (10<z<20), and Reionization (6<z<10) was studied, and its sensitivity to the values ​​of the cosmological parameters, and as well as the physical conditions and composition of the intergalactic environment. The formation of the first H2, HD, and HeH+ molecules in the intergalactic medium and in the Dark Ages and Cosmic Dawn haloes was studied, and the global signals in the spin-vibration lines of these molecules were calculated. Models of the spectral density of radiation of the first light sources, necessary for the complete Reionization of hydrogen at z~6-8, assuming its thermal energy distribution, were constructed. The Cosmic web and the large-scale structure of the Universe were studied using topological analysis and persistent homology. The influence of the circumstellar medium on the spectra of cosmic rays and the non-thermal radiation of supernova remnants was studied. It is shown how the gas density and temperature profiles of the wind-generated bubbles of the supernova remnant, together with the magnetic field and scattering turbulence, regulate the spectra of particles accelerated by supernova remnants. It is shown that the compression of galactic cosmic rays by shock wave fronts of supernova remnants cannot explain their brightness in the gamma range. Constraints on the parameters of the cosmological model with additional interaction between dark energy and dark matter were obtained based on the data of CMB, BAO, and SN Ia observations. The observations were made, and the differential brightness curves of dimmed double stars were obtained based on them, and their main parameters were determined: the orbital period, the heliocentric moments of the Main and Secondary minima of brightness, the O-C displacement of the moments of both minima for the given epoch of observations, etc. Product Description popup.authors Apunevych Stepan Ye. Baran Oleksandra A. Kaserkevych Valerii S. Kulinich Yurii A. Nimchuk Oleksii P. Neomenko Roman H. Permiakova Olha A. Prysiazhnyi Andrii I. Sushch Yurii V. Tsizh Maksym B. popup.nrat_date 2025-02-03 Close