Seminar: The Role of Kinetic Waves in the Solar Wind Evolution

Charged particles constantly stream outward from the Sun to fill the heliosphere. These particles, consisting mainly of protons and electrons, form a plasma called the solar wind. While the general structure of the solar wind was established decades ago, the radial evolution of its properties, such as temperature and velocity distributions, remains poorly understood. Conventional fluid models fail to explain observed solar wind behavior because of its low collisionallity. Therefore, the radial evolution of the solar wind properties must be driven by collisionless processes. In particular wave-particle interactions occuring at kinetic scales are an important regulator of the solar wind properties, because of the strong connection between the electromagnetic fields and the charged particles. We investigate the effect of kinetic waves in the solar wind evolution, demonstrating the necessity of a kinectic treatment to accurately describe the fundamental physics of the heliosphere.