Change in the Orbital Period of a Binary System Due to Dynamical Tides for Main-Sequence Stars

Abstract

We investigate the change in the orbital period of a binary system due to dynamical tides by taking into account the evolution of a main-sequence star. Three stars with masses of one, one and a half, and two solar masses are considered. A star of one solar mass at lifetimes $t=4.57\times10^9$ yr closely corresponds to our Sun. We show that a planet of one Jupiter mass revolving around a star of one solar mass will fall onto the star in the main-sequence lifetime of the star due to dynamical tides if the initial orbital period of the planet is less than $P_{\rm orb}\approx2.8$ days. Planets of one Jupiter mass with an orbital period$P_{\rm orb}\approx2$ days or shorter will fall onto a star of one and a half and two solar masses in the mainsequence lifetime of the star.