Workshop

Understanding the theory of particles in plasmas

On Monday, January 22nd, scientists meet at RUB for the yearly meeting "Plasma and Particle Theory Day" to discuss the theory of particles in plasmas. Understanding the collective behavior of ionized particles is in the focus of research. A particular challenge is to understand how physical collisions of particles and the interactions between ions and electromagnetic fields are included in the various equations to describe the systems. In astrophysics, often these equations are dominated by the interaction of particles with electromagnetic waves. This is the research focus of the Collaborative Research Center SFB1491, "Cosmic Interacting Matters - From Source to Signal", centered at RUB. The research department of Plasmas with Complex Interactions also hosts SFB1316, "Transient Atmospheric Plasmas: From Plasmas to Liquids to Solids". Here, non equilibrium processes in atmopsheric plasmas for species conversion are the topic of research. Compared to astrophysical plasmas, these atmopsheric plasmas are very dense and physical collisions dominate the equations. It is the goal of the Plasma and Particle Theory day to move toward exploring the region in which both terms play a significant role. This is for instance the case in molecular clouds in the Milky way, in which the degree of ionization is as low as ~30% and naturally, collisions become important in the description. Another example is the physics of lightning that can be tested in the plasma lab and for which a briding theory is needed to understand the physics of atmospheric lightning. Once the particle interactions become inelastic, i.e at high energies or at extreme densities like they exist in neutron stars, the classical description needs to be replaced by the quantum mechanical one. Scientists therefore discuss the different methods, how synergies can be build and what the next steps are to build a consistent framework to combine classical and quantum-mechanical interactions.

Figure: Lukas Merten, TP4, RUB