Numerical Simulations of Astrospheres and Cosmic Ray transport inside

Project Description:

An astrosphere is a region of space influenced by the stellar wind—a flow of charged particles emitted by a star. It's essentially a bubble-like area formed by the interaction between the stellar wind and the surrounding interstellar medium. Within this low-density cavity, different boundary layers can be found. The termination shock is the region where the stellar wind slows down from supersonic to subsonic speeds. The boundary of the astrosphere is called the astropause, where the pressure of the stellar wind balances with that of the interstellar medium. A bow shock might also be present—a shock wave that can form ahead of the astrosphere if the star is moving supersonically through space. The importance of an astrosphere lies in its ability to protect planetary systems from high-energy particles known as cosmic rays, which can be harmful to life. With upcoming missions, we are on the verge of detecting and characterizing Earth-like exoplanetary atmospheres for the first time. These planets are most likely to be found around smaller and cooler K- and M-type stars. However, recent observations suggest that their radiation environments may be much harsher than that of the Sun. As a result, these exoplanets are likely exposed to increased levels of stellar radiation, which could affect their habitability—such as through hazardous fluxes of energetic particles. Understanding the stellar radiation field and modeling radiation exposure on a planet's surface is crucial for assessing its potential to support life. In this project, various model simulations will be conducted to understand astrospheric evolution and/or cosmic ray propagation inside these structures. For astrospheric evolution, two different fully 3D magneto-hydrodynamic (MHD) models can be accessed and used, depending on the specific problem. Both models are run on a high-performance computing cluster. To calculate the impact of cosmic rays on Earth-like exoplanets, different cosmic ray particle transport (TPE) models can be utilized depending on complexity. This project is suitable for students interested in running simulations, visualizing results, and working in a Linux-based environment.

Research Area:

General Astrophysical Sciences

Project Level:

Honours

This Project Is Offered At The Following Node(s):

(NWU)

Special Requirements:

This project is suitable for students interested in running simulations, visualizing results, and working in a Linux-based environment.