Photometric analysis and period analysis of the early-type eclipsing binary system TT Aurigae

ABSTRACTPreciselly recorded eclipse times of eclipsing binaries are unique tools toconstruct any O-C graphs which offer a very good analytical method to study binarysystems. One of these methods called ?light-time? effect as observed in early-typeeclipsing binary system TT Aur is the main research title of the present thesis. The O-Cvariation of the TT Aur system, for which light-time effect is recently reported bySimon (1999), is re-analyzed on the basis of new observational data. This analysis givesa new set of parameters of the third body whose evidence can not be confirmed by anyother methods. İnsufficient numbers of data and scatters in the O-C diagram of TT Aurcause some constraints in determining of third body parameters. A new rate of orbitalchange of the eclipsing binary is also calculated as ΔP P = 1.1x10 −3 s / year. The resultsare compared to the others given in the literature.Large number of minimum times are needed to deduce more precise parametersof third body in the TT Aur system.Key Words: Eclipsing Binaries, Period Analysis, TT AurII