The bachelor thesis aims at developing a numerical code modelling relativistic profiles of K-alpha iron spectral lines radiated from the surface of oblate neutron stars in the Schwarzschild spacetime. The surface of the oblate neutron star was approximated by an ellipsoid with equatorial and polar semi-axis sizes, which were determined by the results of numerical modelling of the neutron star structure. The obtained line profiles were compared with the published results of a more accurate method. When developing the numerical code, attention was paid to its parallelization, optimization and hence the speed of calculation. The effect of neutron star oblateness on the resulting spectral curves was also analysed.
Full-text PDF here. (in czech language)
This bachelor thesis is devoted to studying motion of test particles around radiating compact object. This motion is strongly influenced by interaction of particles with radiation field, mainly through the Poynting-Roberson effect, causing loss of angular momentum – thus, particles cannot remain on a stable circular orbit. Thesis is mainly focused on vertical motion of particles around the equatorial plane of Kerr metric, and the influence of spin and luminosity at properties of trajectories.
Full-text PDF here. (in czech language)
The thesis is focused on developing an analytical approximation to construct relativistic projection of the surface of spherically symmetric neutron stars in the Schwarzschild spacetime. Based on the analytical expression of the transfer function, a numerical code was developed for modeling the relativistic projection of neutron star’s surface and relativistic spectral profiles of the iron K alpha lines. The influence of gravitational lensing and gravitational and Doppler shifts on the resulting spectral profiles was analyzed. The dependence of spectral profiles on the angular radius of the radiating surface of the neutron star was also analyzed.
The bachelor thesis is devoted to computer modeling of thermal conditions of exoplanets orbiting in close vicinity of the event horizon of rotating black holes. Based on the existing theory describing the influence of the cosmic microwave background by the extreme gravitational field, the temperature of the exoplanets and its dependence on the orbital radius, the black hole spin and other parameters are examined. The possibility of existence of a habitable zone in the vicinity of supermassive black holes is analyzed.
