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Information × Registration Number 0224U032951, (0124U004029) , R & D reports Title Tomography of the Dark Ages and Cosmic Dawn in the lines of hydrogen and the first molecules as a test of cosmological models popup.stage_title Глобальні сигнали в лінії 21 см та лініях перших молекул з епохи Темних віків Head Novosyadlyj Bohdan S., Доктор фізико-математичних наук Registration Date 12-12-2024 Organization Ivan Franko National University of Lviv popup.description1 To investigate the formation of global signals and power spectra of spatial intensity fluctuations in the 21 cm line of hydrogen and ro-vibrational lines of the first molecules in the Universe at 6<z<300 in various cosmological models. To build models of the spectral energy distribution of radiation of the first light sources and evaluate local variations of signals from the Cosmic Dawn and their statistical distributions across the sky based on model of the formation of the first light sources. popup.description2 In the reporting stage, we performed work on calculating the conditions and dynamics of the evolution of matter in the cosmological era of the Dark Ages. We calculated the kinetics of the formation of the first molecules H2, HD, and HeH+ both in the standard cosmological model and in models with the presence of primary magnetic fields and self-annihilating and decaying dark matter particles as additional sources of heating and ionization of gas in the early Universe. We calculated the intensities of the sky glow (global signals) in the lines of the first molecules against the background of cosmic microwave background radiation. The results obtained show that the signal from the first molecules in the standard cosmological model is a broad absorption line in the spectrum of cosmic microwave background radiation and is formed in the Dark Ages. In models with additional heating sources, absorption decreases, and when the gas is heated above the temperature of cosmic microwave background radiation, it turns into emission. The brightness temperature (i.e., intensity) of the 21 cm hydrogen line formed in the Dark Ages and Cosmic Dawn has been calculated in both the standard cosmological model and in models with additional heating and ionization. The results show that the Dark Ages signal is sensitive to the parameters of self-annihilation and decay of dark matter particles, while the Cosmic Dawn signal is also sensitive to the characteristics of the radiation of the first sources. We show that observations of the 21 cm line in both the decameter and meter wavelength ranges are required to constrain dark matter models and first source formation scenarios. Calculations performed using the author's codes were also verified by calculations using the publicly available ARES and DM21cm codes. We built numerical models and investigated the formation of ionized hydrogen zones around star-forming regions of early galaxies. Product Description popup.authors Koval Danylo M. Kopach Pavlo I. Kulinich Yurii A. Melekh Bohdan Ya. Rudakovskyi Anton V. Tsizh Maksym B. popup.nrat_date 2024-12-12 Close