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Information × Registration Number 0219U003555, 0116U000829 , R & D reports Title Investigations of gravitational lenses: cosmological parameters and physics of extragalactic objects popup.stage_title Head Olexandr Zheleznyk, Registration Date 23-01-2019 Organization Kharkov National University named after V.N. Karazin popup.description2 The object of study - the phenomenon of gravitational lens, quasars and active galaxy nuclei. The goal of the work - to obtain the new astrophysical information using investigation of objects created by gravitational lensing and modeling of active galaxy nuclei. The light propagation through an optically-thick medium of lens galaxy had been considered, taking into account a pairs of point-mass stars, separated by a significant distance along the line of sight. It is shown that in framework of this model a noticeable increase of scattering of quasar radiation is possible. The helicity of a thin toroidal vortex in the presence of torsion had been considered. It is shown that relation of the helicity with circulations along the guide and forming of torus depends on the distribution of the azimuthal velocity in the core of a swirling vortex ring. In the case of an inhomogeneous torsion this relationship is different from the known Moffat relationship. The evolution of a self-gravitating clumpy torus in the gravitational field of the central mass of an active galactic nucleus (AGN) in the framework of the N-body problem had been considered. A scenario of torus formation related with the beginning of the AGN stage is discussed. Obtained modeling results is compared to observational data. The problem of motion of particles in galaxies with ring-like structures of Hoag object-type where the mass of the central galaxy is comparable to the mass of the ring had been considered. It has been shown that in such a system exists a circle of unstable equilibrium, "Lagrange circle", and stable circular orbits exist only in a certain area limited to the last stable circular orbit. It is shown that in galaxies with massive ring structures (Hoag type objects) a gap in the distribution of matter can be formed. With the use of the newly developed method of analysis of lightcurves of lensed quasar components an improved estimation of time delay for Q2237+0305 system with absolute errors better than ± 2 days had been obtained. Short-time scale variations of the brightness of components of Q2237 + 0305, related to the intrinsic variability of the quasar-source, has been revealed. The analysis of the lightcurves obtained earlier from observations at the Maidanatk Observatory allowed to conduct a reverberative mapping of the quasar source Q2237 + 0305. In particular, the possibility of the existence of extended structure around accretion disk that effectively radiates in the optical range has been confirmed. The new method of photometry of compact systems of point sources was developed. Using this method a monitoring data of gravitationally lensed quasar Н1413+117 had been processed. Internally consistent estimation of time delays of components obtained as well as recorded microlensing events in this system. The new method for the search of gravitationally lensed quasars using the data of multicolor sky surveys had been proposed. Preliminary data processing of SDSS and KiDS sky surveys has been performed, lists of candidate systems for subsequent confirmatory observations have been generated. The first confirmatory observations of several candidates were conducted, resulting in the discovery of 3 new systems of gravitationally-lensed quasars (SDSSJ1442+4055, SDSSJ1617+3827 and KiDS0239-3211). Product Description popup.authors O. Кочетов І. Сінельніков В. Конічек В. Цвєткова Л. Бердіна О. Баннікова О. Железняк О. Сергєєв popup.nrat_date 2020-04-02 Close