| Name: | Sakshi Gupta |
| Affiliation: | Indian Institute of Science Education and Research, Kolkata |
| Conference ID : | ASI2023_157 |
| Title : | Magnetic Interaction of Stellar Wind and (Exo)planetary Environments: Implications for Atmospheric Losses and Habitability |
| Authors : | Sakshi Gupta, Arnab Basak and Dibyendu Nandi |
| Mode of Presentation: | Oral |
| Abstract Category : | Stars, ISM and Galaxy |
| Abstract : | The long-term evolution of stellar magnetic activity shapes the magnetosphere-atmosphere of the orbiting planets impacting their habitability. We perform three-dimensional magnetohydrodynamic simulations followed by a detailed parameter space study to understand how the variation in stellar wind and planetary magnetic field strength regulates the planetary magnetic field topology and atmospheric mass loss rate. We find that the relative strength of planetary magnetic field with respect to that of stellar wind plays a critical role in determining the steady-state magnetospheric configuration and atmospheric erosion. Either an enhancement in stellar wind magnetic field or a reduction in planetary magnetospheric strength leads to day-side magnetic field accumulation similar to an induced magnetosphere. The magnetotail opens up leading to the formation of Alfvén wings in the night-side wake region. We identify reconnection processes and wind conditions that lead to the bifurcation of the current sheet in the magnetotail. With increasing stellar wind magnetic field strength, the day-side reconnection point approaches the planet, thereby increasing the mass-loss rate. Our study has far reaching implications in the context of star-planet interaction and (exo)planetary habitability. |
