No abstract

Atmospheric modeling is used to build synthetic spectral energy distributions (SEDs) for the individual components of the speckle interferometric binary system HD375. These synthetic SEDs are combined together for the entire system and compared with its observational SED in an iterated procedure to achieve the best fit. Kurucz blanketed models with the measurements of magnitude differences were used to build these SED's. The input physical elements for building these best fitted synthetic SEDs represent adequately enough the elements of the system. These elements are: T a eff = 6100±50 K, T b eff = 5940±50 K, log ga = 4.01±0.10, log g b = 3.98±0.10, Ra = 1.93±0.20R⊙ ,.50, La = 4.63±0.80L⊙ and L b = 3.74±0.70L⊙ depending on new estimated parallax π = 12.02 ± 0.60 mas. A modified orbit of the system is built and compared with earlier orbits and the masses of the two components are calculated as Ma = 1.35M⊙ and M b = 1.25M⊙. Depending on the estimated physical and geometrical elements of the system, which are assured by synthetic photometry, we suggest that the two components are evolved subgiant (F8.5 IV & G0 IV) stars with age of 3.5 Gy formed by fragmentation.

Atmospheric modeling and dynamical analysis of the components of the visually close binary system (VCBS) HD6009 were used to estimate their individual physical and geometrical parameters. Model atmospheres were constructed using a grid of Kurucz solar metalicity blanketed models, and used to compute the individual synthetic spectral energy distribution (SED) for each component separately. These SEDs were combined together to compute the entire SED for the system from the net luminosities of the components a and b located at a distance d from the Earth. We used the feedback modified parameters and iteration method to get the best fit between synthetic and observational entire SEDs.The physical and geometrical parameters of the system's components were derived as:15M⊙, La = 6.80 ± 0.75L⊙, L b = 6.09 ± 0.75L⊙ and π = 14.43mas dynamical parallax. The system is shown to be consist of G6 IV primary and G6 IV secondary components.