What is nuclear fusion and why do we need it? This is a brief introduction to nuclear fusion and plasma physics and my Master thesis at the Max Planck Institute of plasma physics. I will explain why energetic particles are needed for fusion future experiments and why we already know that they will want to leave the reactor.

These energetic particles interact with the background plasma and can give rise to a novel type of plasma mode: The energetic particle geodesic acoustic mode (EGAM). The properties of this mode are not well understood and it is unknown if theory and experiment agree across different devices.

I will present my results from the analysis of EGAMs at ASDEX Upgrade, a large nuclear fusion reactor experiment near Munich.