Thesis Defense |
Events on Friday, June 25th, 2021
- The Formation of Parallel and Perpendicular Collisionless Shocks on the Big Red Ball
- Time: 10:30 am
- Place: B343 Sterling Hall
- Speaker: Doug Endrizzi, Physics PhD Graduate Student
- Abstract: Collisionless shocks are common in space environments. Unlike collisional shocks, where the dissipation of flow kinetic energy into thermal energy is well described by the Rankine-Hugoniot shock jump conditions, collisionless shocks are often not: they can have an unequal partition of energy between particle species, produce electromagnetic waves and radiation, and even accelerate cosmic rays. A good understanding of the structure of such shocks will help interpret many astrophysical systems. But producing collisionless shocks in the laboratory to test theoretical models and simulations is a challenge. To be presented are results from laboratory experiments exploring shocks that are both parallel and perpendicular to the background magnetic field. Two characteristic collisionless shock dissipation mechanisms were observed together in experiment for the first time: reflected ions and large amplitude Whistler waves. This provides nice experimental corroboration of the ‘pulsation shock’ model of the Earth’s quasi-parallel bow shock. Future experimental work will be suggested.
- Host: Cary Forest, Faculty Advisor