Khan S. Modeling and analysis of spectra of Ap stars

The methodology of modeling of spectra of Ap stars with individualized and stratified abundances in magnetic stellar atmospheres is described in the thesis. The magnetic model atmosphere with individualized abundances of Ap star (like betaCrB) was calculated. It is shown that anomalous Zeeman splitting of spectral lines in horizontal magnetic field cause a number of flux depression features which are characteristics of the many magnetic Ap stars. The model atmosphere of Ap star HD101065 with extreme REE abundances was calculated for the first time. The preliminary abundance analysis, the rotation velocity and microturbulence of Ap star HD52696 were determined for the first time. Field of use: astrophysics.