Precise space-based photometry from the Transiting Exoplanet Survey Satellite results in a huge number of exoplanetary candidates. However, the masses of these objects are unknown and must be determined by ground-based spectroscopic follow-up observations, frequently revealing the companions to be low-mass stars rather than exoplanets. We present the first orbital and stellar parameter solutions for five such eclipsing binary-star systems using radial-velocity follow-up measurements together with spectral-energy-distribution solutions. TOI-416 and TOI-1143 are totally eclipsing F+M star systems with well-determined secondary masses, radii, and temperatures. TOI-416 is a circular system with an F6 primary and a secondary with a mass of M2=0.131(8)M⊙. TOI-1143 consists of an F6 primary with an M2=0.142(3)M⊙ secondary on an eccentric orbit with a third companion. With respect to the other systems, TOI-1153 shows ellipsoidal variations, TOI-1615 contains a pulsating primary, and TOI-1788 has a spotted primary, while all have moderate mass ratios of 0.2-0.4. However, these systems are in a grazing configuration, which limits their full description. The parameters of TOI-416B and TOI-1143B are suitable for the calibration of the radius-mass relation for dwarf stars.
@article{arxiv.2408.06897,
title = {Five new eclipsing binaries with low-mass companions},
author = {J. Lipták and M. Skarka and E. Guenther and P. Chaturvedi and M. Vítková and R. Karjalainen and J. Šubjak and A. Hatzes and A. Bieryla and D. Gandolfi and S. H. Albrecht and P. G. Beck and H. J. Deeg and M. E. Everett and J. Higuera and D. Jones and S. Mathur and Y. G. Patel and C. M. Persson and S. Redfield and P. Kabáth},
journal= {arXiv preprint arXiv:2408.06897},
year = {2024}
}