A comprehensive study of internal gravity waves in magnetized solar atmosphere using numerical simulations

• Applicant: Professor Dr. Markus Roth
• Subject Area: Astrophysics and Astronomy
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 317162715

The complex magnetic atmosphere of the Sun supports different types of waves. These magneto-atmospheric waves are partially responsible for the mass and energy balance of the Sun´s outer envelope. But the magneto-hydrodynamic processes governing the generation, propagation, and dissipation of these waves are poorly understood. A clear knowledge of all the different wave phenomena is vital for solving the various mysteries surrounding the Sun, including the problem of heating of the upper layers. Research in this direction had revived interest in internal gravity waves, which are thought to be capable of transferring sufficient energy to the upper layers to balance the energy lost through radiation. However, observations of the real Sun show that these waves are suppressed in strong magnetic field regions. This raises questions about their global influence as the solar atmosphere is permeated by magnetic fields on every possible scale. Recent work using ray theory show that internal gravity waves can convert to other magneto-atmospheric waves depending on the properties of the magnetized environment through which they propagate. We propose that this coupling can provide a pathway by which internal gravity waves can indirectly contribute to the overall energy budget of the solar atmosphere. With the help of state-of-the-art numerical simulations, we will carry out a comprehensive study of the generation and propagation of internal gravity waves in realistic solar models (first and second part of the project). Investigating the properties of these waves in an atmosphere with spatially and temporally varying magnetic fields will bring us more close to the actual processes that happen on the Sun. As a major step forward, we will use our simulated models to synthesize data that mimic real observations of the Sun and study their properties from an observer´s viewpoint (third part). This will lead to a better interpretation of current and future observations and will further advance our knowledge on the role of waves in solar atmosphere. The expected significance of the proposed work on a broader context is to connect the missing link in our understanding of all the different wave phenomena in the solar atmosphere and their individual role in maintaining the energy balance, either directly or indirectly, and their potential for revealing the nature of magnetized solar atmosphere.

• DFG Programme: Research Grants
• International Connection: USA
• Cooperation Partner: Professor Jason Jackiewicz, Ph.D.