How does the mass and activity history of the host star affect the population of low-mass planets?

TL;DR

This study investigates how the mass and activity history of host stars influence the atmospheric evolution and survival of low-mass, sub-Neptune-like planets, revealing that stellar properties significantly affect planetary atmospheres, especially around more massive stars.

Contribution

It introduces a comparative framework combining planetary evolution models with atmospheric escape prescriptions to analyze the impact of stellar mass and history on planetary atmospheres.

Findings

Planets around solar-mass stars are more likely to retain their primordial atmospheres.

Atmospheric survival patterns are similar across different stars but differ qualitatively with stellar mass.

Initial planetary temperature uncertainties mainly affect planets with extreme atmospheric mass-losses.

Abstract

The evolution of the atmospheres of low and intermediate-mass planets is strongly connected to the physical properties of their host stars. The types and the past activities of planet-hosting stars can, therefore, affect the overall planetary population. In this paper, we perform a comparative study of sub-Neptune-like planets orbiting stars of different masses and different evolutionary histories. We discuss the general patterns of the evolved population as a function of parameters and environments of planets. As a model of the atmospheric evolution, we employ the own framework combining planetary evolution in MESA with the realistic prescription of the escape of hydrogen-dominated atmospheres. {We find that the final populations look qualitatively similar in terms of the atmospheres survival around different stars, but qualitatively different, with this difference accentuated for planets orbiting more massive stars. We show that a planet has larger chances of keeping its primordial atmosphere in the habitable zone of a solar mass star compared to M or K dwarfs and if it starts the evolution having a relatively compact envelope.} We also address the problem of the uncertain initial temperatures (luminosities) of planets and show that this issue is only of particular importance for planets exposed to extreme atmospheric mass-losses.