Physics

Physics

General Physics Research Projects

Alfven Wave Parametric Decay

Feiyu Li, NMC Research Scientist
Sean Fu, LANL Staff Scientist and NMC Research Scientist
Seth Dorfman, Space Science institute Research Scientist

Supported by NASA grants commencing 2023, the team will aim for the first observation of Alfven wave parametric decay in the laboratory. Alfven waves are a major carrier of energy over long distances in space plasma. The dissipation of Alfven wave energy through nonlinear interactions may be powerful enough to accelerate the solar wind — a stream of plasma particles ejected from the Sun. The Alfven wave parametric decay instability (PDI) — where a large amplitude Alfven wave decays into a daughter Alfven wave and a sound wave — is widely conceived to be a key energy dissipation mechanism, driving plasma heating and turbulence. Yet, observational evidence of PDI in space is not well established due to complex space environments and limited spacecraft explorations.

These projects will take advantage of the Large Plasma Device (LAPD) at UCLA — 20-meter long linear device, and conduct PDI studies under well controlled conditions. In the past two years, the team have developed 3D kinetic simulations that are tailored to model LAPD Alfven wave studies using realistic geometries and wave and plasma conditions. These capabilities will enable detailed characterization and prediction of LAPD conditions needed to drive PDI. The projects will also devise novel methods to measure the growth rates of the instability and perform detailed scaling studies of PDI versus the broad LAPD parameters. The study will aid our understanding of the role of PDI in the solar terrestrial plasma system and help benchmark existing theories and our computational models.

PAST PROJECTS

  • CRCNS – Microimaging/modeling of Retinal Responses Measured with Laser Magnetometers
  • Effects of the Field Shear and Flow Shear on the Kinetic Physics and Particle Acceleration of Relativistic Reconnection
  • PLASMA PHYSICS: Turbulence and Particle Energization in Low-Beta Plasmas