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Information × Registration Number 0204U003177, 0101U002792 , R & D reports Title Problems of relativistic astrophysics and cosmology popup.stage_title Head Dudinov V., Registration Date 16-02-2004 Organization Kharkov National University named after V.N.Karazin popup.description2 Objects of investigations are the cosmological models of arbitrary number of measuring, cosmological periodicities in spectrums of quasars, jets of quasars and radio galaxies, the toroidal vortexes of degenerated gas, physical nature of a radio source Sgr A *, second derivative of order two of gravitational potential. Goal of the work is a finding of solutions of the Einstein's gravitation equations for cosmological models of arbitrary number of measuring, finding of periodicities in spectrums of quasars, definition parameters of jets, deriving of a stability criterion of a toroidal vortexes of degenerated gas, finding of radiation Sgr A* in view of nuclear burning of hydrogen on a surface, viscosity of plasma and dissipation of energy for account Coulomb collisions of protons, to finish development of a compact gravitational gradiometer. Methods of investigation are a method of a spectrum analysis at searching cosmological periodicities, theoretical and numerical model operation at definition of parameters of jets, numerical solution of the differential equations at finding of a radiation spectrum of Sgr A*. At research of gradiometer sensitivity the numeral methods of a signal handling were used. The precise solution of the Einstein's equations for models of the Universe of arbitrary measuring number for models "vacuum + matter" and "vacuum + radiation" is found. In complete and selection samples of quasars the periodicities at four frequencies are detected. In a radio spectral index of quasars the period is detected, witch consists on quantity with a distinguished length of large-scale structure of the Universe. The estimated parameter of density in flat model amounted 0.23 ± 0.03 (at a level 2?). The way of getting of jet physical parameters (such as a magnetic field strength, jet or knot velocity etc.) were offered on the basis of diffusion model for the moving point source of relativistic electrons located in the jet knots. The maps of distribution of intensity and spectral index calculated within the framework of the moving knot model with the observational data for knots A and B in jet of M87, for the southern component of jet of microquasar 1E1740.7-2942 in the Galactic Center and number of other sources have been calculated, and also have been determined their parameters. The similarity and distinction between the images of jets of extragalaxy sources in a radio and x-ray bands created by the same distribution of relativistic electrons due to synchrotron (for radio) and inverse Compton scattering (for X-ray) is discussed. Furthermore, the case of spatially homogeneous purely Compton losses on relic radiation in diffusion model of electron propagation from moving source of injection - jet knot or hot spot is considered. The evolution of self-gravitating toroidal vortex ring, similar on its early stage of the Maxwell vortex, has been examined. The contraction has two stages: thin and compact vortices. The thin vortex evolution on the small radius occurs quicker than on the big one. The equilibrium conditions differ from those for disk and sphere. The solutions for the degenerated electron and neutron gas of toroidal vortexes have been obtained and analyzed. The limit Landau-Chandrasekhar mass was found dependent on the vortex velocity circulation, the mass exceeding the value for a non-rotating case. The development to a laboratory experimental model of a compact gravitational gradiometer based on magnetic suspension is completed. On the device, located in the evacuated chamber, at pressure 10-8 millimeter of mercury and temperature 293К it was possible to level sensitivity 0.01 Eotvos. The radiation contribution of Sgr A*, stipulated by nuclear burning of hydrogen, inhibiting of a stream in the upper layer of an atmosphere, viscosity and Coulomb collisions of protons in a stream is obtained. Product Description popup.authors popup.nrat_date 2020-04-02 Close