• Mr. Colin Adams
  • University of New Mexico
  • 104D Surge Building
  • 4:00 p.m.
  • Faculty Host: Dr. Eric Paterson

Studies of laboratory plasmas are important to advances in many fields, including astrophysics, propulsion, and fusion.  The parameter space of laboratory plasmas varies widely, covering a factor of roughly 10^5 in temperature and more than a factor of 10^20 in density.  Plasmas generated by a spacecraft thruster typically have an ion density of only 10^10 particles per cubic meter or less, while a laser-driven fusion experiment could have well in excess of 10^30.  The parameter space for astrophysical plasmas covers even lower densities, down to only 100 particles per cubic meter in the interstellar medium.  This presentation will focus on two laboratory experiments.  The first investigates flow-stabilization in a plasma confinement configuration applicable to a Z-pinch fusion thruster concept, which could one day be used for a high-speed deep-space mission.  The second attempts to emulate and understand the physical processes involved in astrophysical collisionless shocks, which are thought to accelerate particles to high energies, a mechanism perhaps responsible for 40% of cosmic rays in the universe.  The experiments which will be discussed have temperatures ranging from 1 - 300 electronvolts and densities from 10^19 - 10^23 particles per cubic meter.  The diagnostic instruments utilized to understand the state and dynamic behavior of the plasma will be discussed, as well as the challenges of covering even this relatively limited range of plasma parameters.