Towards a New Prescription for the Tidal Capture of Planets, Brown Dwarfs and Stellar Companions

TL;DR

This paper investigates the orbital evolution and capture conditions of planetary and stellar companions during the red giant phase, providing a new prescription for capture radius and timescales across a range of masses.

Contribution

It introduces a new model for the capture radius and timescales that accounts for a non-constant f parameter during stellar evolution.

Findings

Mass loss during the red giant branch has minimal impact on semi-major axis.

For a 1.5 solar mass star, the capture radius is about 300 R or 1.4 AU.

Initial results align with previous studies.

Abstract

We study the evolution of the orbit of a planetary companion as the primary star evolves during the red giant branch phase. Our aim is to determine a prescription for the capture radius and capture timescales for companions in a wide range of masses, from planet to star, including the effect of a non constant f parameter. Our initial results reproduce past findings. According to our study the mass-loss during the red giant branch does not significantly affect the semi major axis of the planet and for a 1.5 M star the capture radius is approximately 300 R or 1.4 AU.