The Influence of Coronal Mass Ejections on the Gas Dynamics of the Atmosphere of a "Hot~Jupiter" Exoplanet

TL;DR

This study uses 3D simulations to show that coronal mass ejections can significantly increase atmospheric mass loss in hot Jupiter exoplanets, potentially affecting their evolution.

Contribution

It provides the first detailed numerical analysis of how CMEs impact the gas dynamics and mass loss of hot Jupiter atmospheres.

Findings

CME events can tear off outer atmospheric layers beyond the Roche lobe.

Mass-loss rate increases by approximately 11 to 14 times during CMEs.

CME-induced atmospheric loss may influence exoplanet evolution.

Abstract

The results of three-dimensional numerical simulations of the gas dynamics of the atmosphere of a "hot Jupiter" exoplanet during the passage of a coronal mass ejection (CME) from the central star are presented. These computations assumed the parameters for the stellar wind and the CME to be typical of the solar values. The characteristic variations of the flow pattern are considered for quasi-closed and closed (but appreciably distorted by the gravitational influence of the star) gaseous envelopes of the exoplanet. It is shown that a typical CME is sufficient to tear off the outer part of an asymmetric envelope that is located beyond the Roche lobe and carry it away from the exoplanet. This leads to a substantial increase in the mass-loss rate from the exoplanet envelope during the passage of CMEs. The mass-loss rate grows by about a factor of 11 for a closed envelope, and by about a factor of 14 for a quasi-closed envelope. Possible evolutionary consequences of the loss of part of the atmosphere during the passage of CMEs are discussed.