Detailed evolutionary models for twins in sight of new spectral data: AN Cam, RS Ari, and V455 Aur

Abstract

ABSTRACT We present the evolutionary scenarios for three eclipsing twin (q(M2/M1) ∼1) binary systems using their combined spectroscopic and photometric data. Using accurate TESS photometric data, RV measurements, and spectroscopic data enabled us to calculate fundamental parameters, such as mass and radius, better than 2 per cent. The temperature of each component and metallicity of the systems have been obtained via high-resolution spectra. According to our spectral analysis, the metallicity values of AN Cam, RS Ari, and V455 Aur are [M/H] =  0.00 ± 0.12, 0.05 ± 0.08, and −0.07 ± 0.07, respectively. Using the derived metallicity for each system, initial orbital parameters, and detailed evolutionary status of these three systems are calculated with high precision by using mesa. According to our analysis, both components of AN Cam have passed the terminal-age main sequence (TAMS), the primary component of RS Ari is in the giant phase while the secondary component has passed the TAMS, finally, both components of V455 Aur are still on the main sequence. The current ages of the three systems AN Cam, RS Ari, and V455 Aur are 3.0, 3.3, and 1.4 Gyr, respectively, and they will approximately start to transfer mass between components in 400, 250, and 2700 Myr, respectively.