Detached eclipsing binaries in compact hierarchical triples: triple-lined systems BD+442258 and KIC 06525196

ABSTRACT Compact hierarchical triples (CHTs) are systems with the tertiary star orbiting inner binary in an orbit shorter than 1000 d. CHT eclipsing as its can help us extract a multitude of information about all three stars system. In this study, we use independent observational techniques to estimate orbital, stellar, and atmospheric parameters two triple-lined CHT: BD+44 2258 KIC 06525196. We find that masses $1.011\pm 0.029$, $0.941\pm 0.033$, $0.907\pm 0.065 \, {\rm M}_{\odot }$ while 06525196 estimated $1.0351\pm 0.0055$, $0.9712\pm 0.0039 $, $0.777\pm 0.012 }$. Using spectral disentangling, obtained individual spectra combined it light-curve modelling obtain radii, metallicities, temperatures. stellar evolution models from mesa, constrain log(age) be 9.89 9.49 for Two found sub-giants main-sequence stars. mutual inclinations certain angles using numerical integration. Integrating tidal interaction schemes models, is stable But merges within 550 Myr. The time merger affected by orientation tertiary, even rushing collapse ∼100 Myr when inclination close 90○.