The Distribution of Semidetached Binaries. I. An Efficient Pipeline

Semidetached binaries are in the stage of mass transfer and play a crucial role in studying the physics of mass transfer between interacting binaries. Large-scale time-domain surveys provide many light curves of binary systems, while Gaia offers high-precision astrometric data. In this paper, we develop, validate, and apply a pipeline that combines the Markov Chain Monte Carlo method with a forward model and DBSCAN clustering to search for semidetached binaries and estimate the inclination, relative radius, mass ratio, and temperature ratio of each using light curves. We train our model on the mock light curves from Physics of Eclipsing Binaries (PHOEBE), which provides broad coverage of light-curve simulations for semidetached binaries. Applying our pipeline to Transiting Exoplanet Survey Satellite sectors 1-26, we have identified 77 semidetached binary candidates. Utilizing the distance from Gaia, we determine their masses and radii with median fractional uncertainties of similar to 26% and similar to 7%, respectively. With the added 77 candidates, the catalog of semidetached binaries with orbital parameters has been expanded by approximately 20%. The comparison and statistical results show that our semidetached binary candidates align well with the compiled samples and the PARSEC model in T eff-L and M-R relations. Combined with the literature samples, comparative analysis with stability criteria for conserved mass transfer indicates that similar to 97.4% of samples are undergoing nuclear-timescale mass transfer, and two samples (GO Cyg and TIC 454222105) are located within the limits of stability criteria for dynamical- and thermal-timescale mass transfer, and are currently undergoing thermal-timescale mass transfer. Additionally, one system (IR Lyn) is very close to the upper limit of delayed dynamical-timescale mass transfer.