Photometric and Spectroscopic Studies of Two Early-Type Eclipsing Binaries

Abstract

Using high-precision photometric data from TESS, medium resolution spectroscopic data from LAMOST, and long-term eclipse timings, we provide orbital parameters for two early-type detached eclipsing binary systems: TYC 3740-2072-1 and TYC 2888-780-1, and analyze the orbital period variations and evolutionary status of these two targets. TYC 3740-2072-1, with a spectral type of B1V, consists of a $6.914 M_\odot$ subgiant and a $6.233 M_\odot$ main-sequence component. It is expected to evolve into a semi-detached binary, potentially serving as a progenitor of a Type Ia supernova. TYC 2888-780-1 has a spectral type of A3 and consists of two main-sequence components with masses of $1.682 M_\odot$ and $1.673 M_\odot$, respectively. It is undergoing stable evolution. Through eclipse timing analysis, we find that both targets exhibit apsidal motion effects, with observed AM rates of $\dot{\omega}_{obs} = 0.0412~\text{deg}~\text{cycle}^{-1}$ and $\dot{\omega}_{obs} = 0.0205~\text{deg}~\text{cycle}^{-1}$, respectively. Additionally, TYC 2888-780-1 exhibits orbital period variations, which we attribute to the light travel time effect caused by a third body, the minimum mass of this third body is estimated to be $0.598 M_\odot$.