Updated Absolute Parameters and Kinematics of IS CMa

TL;DR

This study precisely determined the fundamental parameters, distance, and orbital characteristics of the eclipsing binary IS CMa using combined photometric and spectroscopic data, revealing its age and Galactic population membership.

Contribution

The paper provides the first precise measurements of masses, radii, distance, and orbital period variation of IS CMa using TESS data and Wilson-Devinney analysis, and assesses its evolutionary status and Galactic orbit.

Findings

Masses: M1=1.58 M☉, M2=0.48 M☉

Distance: 92.7 pc, with an orbital period increasing at 1.09×10⁻⁷ day/yr

Age estimated at 1.3 Gyr, member of the young thin-disc population

Abstract

Eclipsing binary systems are significant objects for astrophysics in that direct observations can determine the fundamental parameters of stars. In this study, we determined precisely the fundamental parameters of the binary component stars obtained by simultaneous analysis of radial velocities and the {\it TESS} light curve using the Wilson and Devinney code. Following the analysis, the masses and radii of the primary and secondary components were determined as $M_{1}= 1.58\pm 0.01M_\odot$, $M_{2}= 0.48\pm0.02M_\odot$, and $R_{1}=1.93\pm 0.01R_\odot$, $R_{2}= 1.14\pm 0.01 R_\odot$, respectively. Furthermore, the distance of IS CMa is calculated as $92.7\pm6.5$ pc. On the basis of the analysis of the mid-eclipse times, it was found that the variation in the orbital period is represented by an upward parabola. It has an increasing rate of $dP/dt$ = 1.09 $\times$ 10$^{-7}$ day yr$^{-1}$. Using PARSEC stellar evolutionary tracks and isochrones with solar metallicity were estimated the age of IS CMa as $1.3\pm0.1$ Gyr. Kinematic and Galactic orbital parameters of IS CMa were obtained from the astrometric and spectroscopic data of the system. The Galactic orbit analysis reveals that IS CMa formed inside the solar circle and it is a member of the young thin-disc population.