Speckle interferometric binary system HD375; Is it a sub-giant binary?

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.

Complex Analysis of the Stellar Binary HD25811: A Subgiant System

“…The observational SED of the entire system was taken from Al-Wardat (2002b) (Figure 3). It shows some strong lines and depressions, especially in the red part of the spectrum (around λ6867Å, λ7200Å, and λ7605Å).…”

Comparison of Gaia and Hipparcos parallaxes of close visual binary stars and the impact on determinations of their masses

“…We investigated how measurements of the dynamical masses of the selected CVBSs are affected by the distances inferred from the parallax measurements in each of the catalogues discussed above. We also compared these results with masses estimated from two different indirect methods: Malkov’s photometric masses (Malkov et al 2012a,b) and Al-Wardat’s multi-parameter approach for analysing CVBSs (Al-Wardat 2002a,b, 2007; Al-Wardat et al 2014b; Al-Wardat, Widyan, & Al-thyabat 2014a; Al-Wardat et al 2016, 2017; Masda, Al-Wardat, & Pathan 2018a; Masda, Al-Wardat, & Pathan 2018c). The latter is a computationally complex method employing colours, colour indices, and magnitude differences of the system along with its parallax to build individual synthetic spectral energy distributions (SED) for each component of the system.…”

Physical and geometrical parameters of the binary system gliese 150.2

“…Table III lists the synthetic Jonson, Strömgren and Tycho magnitudes and color indices, which were calculated by [3,5], depending on the observational SED. [11] introduced a preliminary orbit of the system depending on 12 interferometric measurements and the first Hipparcos data point with a period of about 15 years.…”

“…FIG.3: Dotted line: the entire observational SED in the continuous spectrum of the system[3]. Solid lines: the entire computed SED of the two components, the computed flux of the primary component with T eff = 5625 ± 75 K, log g = 3.75 ± 0.25, R = 2.69 ± 0.30R⊙, and the computed flux of the secondary component with T eff = 5675 ± 75 K, log g = 3.75 ± 0.25, R = 2.42 ± 0.30R⊙ and d = 69.31 pc.…”