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Information × Registration Number 0213U001685, 0110U001033 , R & D reports Title Investigation of gravitational lens systems popup.stage_title Head Dudinov Volodimir, Registration Date 23-01-2013 Organization Kharkov National University named after V.N. Karazin popup.description2 The object of investigation: gravitationally lensed quasars, the objects, which are formed by the action of gravitational fields of foreground galaxies, when they are situated close to the line of sight between the quasar and observer. A goal of the research: measurements of magnitudes and color indices of the lensed quasar components, studies of their variations as functions of the time and obtaining new information about: a) spatial structure of quasars. b) properties and composition of lensing galaxy population, c) detection of dark matter and estimation of its relative contribution with respect of the luminous constituent. Methods of investigation: CCD-photometry with the use of various algorithms of image processing (double iterative PSF subtraction, etc.), correlation and Fourier analysis of unevenly sampled data sets, computer simulation of microlensing events, theoretic analysis and simulation of various aspect of gravitational lensing. To analyze gravitational focusing of radiation in the medium with different spatial scales of structural irregularities, a new improved version of the phase screen method was proposed – a generalized phase screen method (GPSM). Behavior of the microlensing amplification coefficient as the function of the microlens location along the sight line was studied considering both the large-scale irregularity of gravitational field (a galaxy), and small-scale ones (microlenses) situated arbitrarily along the sight. From the results of long-term monitoring the values of time delays in systems H 1413+117 and UM673 (Q0142-100) were measured, which provide more exact estimates of the Hubble constant value and more adequate mass distribution model for lensing galaxies. Based on the analysis of long-term observation of Q2237+0305 in filters VRI, a new two-component model for the quasar spatial structure was proposed – a compact central source (the accretion disc) surrounded by essentially larger extended structure with a low surface brightness. Properties of radiation of this structure are discussed. Theoretic investigation of structure of the active galactic nuclei and quasars were continued. The problem of stability of a dusty-gaseous round totus was examined, which can exist around the accretion disc of quasars and explain some observational data. The gravitational potential of the totus was calculated. Product Description popup.authors Вакулік В. Дудінов В. Железняк О. Конічек В. Сєргєєв О. Сінельніков І. Смирнов Г. Цвєткова В. popup.nrat_date 2020-04-02 Close