Bright spectroscopic binaries: II. A study of five systems with orbital periods of days

Abstract

We present a detailed analysis of five bright spectroscopic binary systems (HD 18665, HD 27131, HD 171852, HD 215550, and HD 217427) that have orbital periods of P ≲ 500 days. We determined the complete set of orbital parameters using the toolkit RadVel by analyzing the observed radial velocity curves.To study the properties of the five systems, we also analyzed the intermediate resolution spectra (R ≈ 20,000) observed with the TIGRE telescope and determined the stellar parameters of the primary stars using the toolkit iSpec. With Gaia Early Data Release 3 parallaxes, a correction for interstellar extinction using the 3D dust map, and bolometric corrections, we placed the stars in the Hertzsprung-Russell diagram and compared the positions with stellar evolution tracks calculated with the Eggleton code to determine the masses and ages of the primary stars. They have all evolved to the giant phase. Finally, we were able to determine the masses of the secondary stars and to estimate the orbital inclinations i of the binary systems.

Bright spectroscopic binaries: III. Binary systems with orbital periods of P > 500 days

“…In general, masses and especially ages of stars are difficult to determine because the evolution tracks are very close together during the giant phase. In Figure 1 We performed a consistency check, where we calculated the parallax-related surface gravities of all stars as described in Rosas-Portilla et al (2022) and Jack et al (2022). Knowing the luminosity L, the mass M 1 , and the distance from Gaia DR3, we calculated the surface gravity using basic relations between the stellar parameters.…”

“…We performed a consistency check, where we calculated the parallax‐related surface gravities of all stars as described in Rosas‐Portilla et al (2022) and Jack et al (2022). Knowing the luminosity $$$ L $$$, the mass $$$ {M}_1 $$$, and the distance from Gaia DR3, we calculated the surface gravity using basic relations between the stellar parameters.…”

“…In our previous publications of this series about bright spectroscopic binaries (Jack et al (2020;hereafter Paper I) and Jack et al (2022; hereafter Paper II)), we reported the detection of 19 bright spectroscopic binaries (m V < 7.66 mag) and presented the detailed analysis of ten of these binaries that have periods of P < 500 days. In this third publication of the series, we present a detailed study of the nine remaining bright spectroscopic binaries with periods of P > 500 days.…”

Yet another star in the Albireo system

“…We used the method described in detail in Mittag et al (2018). This method has also been successfully used in studies of spectroscopic binary stars (Jack et al 2020(Jack et al , 2022.…”