The sdBV+dM close-to-synchronization binary TIC 137608661: inclination and thin disk population

Abstract

TIC 137608661 is a new sdBV+dM reflection-effect binary discovered by the TESS space mission with an orbital period of 7.21 hours. In addition to the detailed study of this system that was recently published (Silvotti et al., 2022), this article contains a further discussion on its inclination. Moreover, from the 3D space velocities of the binary obtained from the system’s radial velocity and from the Gaia DR3 proper motion, it is shown that TIC 137608661 belongs to the galactic thin disk population.