English

The visually close binary system HD375; Is it a sub-giant binary?

Solar and Stellar Astrophysics 2013-11-25 v1

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: Teffa=6100±50T_{\rm eff}^{a} =6100\pm50\,K, Teffb=5940±50T_{\rm eff}^{b} =5940\pm50\,K, log ga=4.01±0.10g_{a}=4.01\pm0.10, log gb=3.98±0.10g_{b}=3.98\pm0.10, Ra=1.93±0.20RR_a=1.93\pm0.20 R_\odot, Rb=1.83±0.20RR_b=1.83\pm0.20 R_\odot Mva=3.26±0.40M_{v}^{\rm a}=3.26\pm0.40, Mvb=3.51±0.50M_{v}^{\rm b}=3.51\pm0.50, La=4.63±0.80LL_a= 4.63\pm0.80 L_\odot and Lb=3.74±0.70L L_b= 3.74\pm0.70 L_\odot depending on new estimated parallax π=12.02±0.60\pi=12.02 \pm 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=1.35MM_a =1.35M_{\odot} and Mb=1.25MM_b=1.25M_{\odot}. 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.

Keywords

Cite

@article{arxiv.1311.5737,
  title  = {The visually close binary system HD375; Is it a sub-giant binary?},
  author = {M. A. Al-Wardat and Yu. Yu. Balega and V. V. Leushion and A. A. Taani and N. A. Yusuf and K. S. Al-Waqfi and S. Masda},
  journal= {arXiv preprint arXiv:1311.5737},
  year   = {2013}
}

Comments

The paper has been accepted for publication in Astrophysical Bulletin

R2 v1 2026-06-22T02:12:54.129Z