Instabilities in Collisionless Astrophysical Plasmas

This is a presentation I gave in Trinity 2017 as part of my master's degree at Oxford. The purpose was of the assignment was to delve deeper into a topic, do something of a literature review and derive a couple of interesting plasma instabilities. This topic was right up my alley becayse I had taken a module in Hilary 2017 on collisionless plasma physics, half of which consisted of deriving dispersion relations and determining conditions for when waves can and cannot propagate.

I spent perhaps more time than I should have in the Radcliffe Science Libarary with their copy of Akira Hasegawa's Plasma Instabilities and Nonlinear Effects, which (along with Felix Parra's excellent course notes) served as a guide to me in assembling the presentation. I started from the Vlasov-Maxwell-Landau system and went through the theory to develop the firehose and mirror instabilities and explained a little bit about what some simulations had determined about how these instabilities grow and decay in an astrophysical context, where the magnetic energy is typically much weaker than the thermal energy in the fluid.

My course was in theory of which, to be sure, I am very fond, but it was refreshing to explore the actual physics and how it reflects and dictates what we do huddled in front of whiteboards with sheafs of paper covering every surface.

See my slides here.