Photometric and Spectroscopic Studies of Two Early-type Eclipsing Binaries

Abstract Using high-precision photometric data from the Transiting Exoplanet Survey Satellite, medium-resolution spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopy Telescope, 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 ⊙ subgiant and a 6.233 M ⊙ main-sequence component. It is expected to evolve into a semidetached 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 and 1.673 M ⊙ , respectively. It is undergoing stable evolution. Through eclipse timing analysis, we find that both targets exhibit apsidal motion effects, with observed apsidal motion rates of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mover accent="true"> <mml:mi>ω</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:mi>obs</mml:mi> </mml:msub> <mml:mo>=</mml:mo> <mml:mn>0.0412</mml:mn> <mml:mspace width="1em"/> <mml:mspace width="0.1em"/> <mml:mtext>deg</mml:mtext> <mml:mspace width="0.1em"/> <mml:mspace width="1em"/> <mml:msup> <mml:mrow> <mml:mspace width="0.1em"/> <mml:mtext>cycle</mml:mtext> <mml:mspace width="0.1em"/> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mover accent="true"> <mml:mi>ω</mml:mi> <mml:mo>̇</mml:mo> </mml:mover> <mml:mi>obs</mml:mi> </mml:msub> <mml:mo>=</mml:mo> <mml:mn>0.0205</mml:mn> <mml:mspace width="1em"/> <mml:mspace width="0.1em"/> <mml:mtext>deg</mml:mtext> <mml:mspace width="0.1em"/> <mml:mspace width="1em"/> <mml:msup> <mml:mrow> <mml:mspace width="0.1em"/> <mml:mtext>cycle</mml:mtext> <mml:mspace width="0.1em"/> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> , 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 ⊙ .