Modeling of surface brightness distribution of ER Vul binary star system with Doppler imaging technique

For a better understanding of the nature of magnetic activity and underlying astrophysical processes (eg, the dynamo mechanism) in cold stars, it is important to study the evolution of spots on the surfaces of late spectral stars. The most common observation technique used within the scope of these investigations is to obtain time-dependent high-resolution spectral observations of the active star, and the most effective analysis method is Doppler Imaging Technique. However, binary stars show both more intense and more complex magnetic activity processes due to the high interaction between components (eg spin-orbit coupling). In this context, in order to understand the magnetic activity processes in binary stars, the number of examples in the literature should be increased. In this thesis, the surface brightness distribution of the ER Vul binary star was modeled by Doppler imaging technique. The high-resolution spectral data of the system were obtained using the T80 – Prof. Dr. Berahittin Albayrak Telescope during 8 nights with a R ~ 30000 resolution spectrograph. After achieving high signal/noise (S/N) ratio of the data with the help of the LSD (Least Squares Deconvolution) technique, the velocity profiles were modeled using the DoTS code based on Doppler Imaging Technique, to reconstruct the surface brightness distribution maps of both components of the system.