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

## TL;DR

This study examines how dynamical tides affect the orbital period changes in binary systems with main-sequence stars, showing that close-in planets can spiral into their host stars within stellar lifetimes.

## Contribution

It models the impact of dynamical tides on orbital evolution for main-sequence stars of different masses, considering stellar evolution effects.

## Key findings

- Planets with orbital periods less than ~2.8 days around 1 solar mass stars may fall into the star.
- Planets with periods around 2 days or less can fall into stars of 1.5 and 2 solar masses.
- Dynamical tides significantly influence the orbital decay of close-in planets.

## 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.