Research Progress
Major progress was made in the applicability of stochastic growth theory (SGT) to plasma waves in many regions of space, type II and III solar radio bursts, plasma waves and radio emissions in planetary foreshocks, radiation from the outer heliosphere, and the nature and conditions for nonlinear Langmuir wave processes, linear mode conversion, and other wave-particle processes to occur in space. This research involved analytic plasma theory, analysis and interpretation of spacecraft data, and comparisons between theory and observation. A foreshock is the region upstream of and magnetically connected to a shock waves, thereby containing energized particles reflected and accelerated at the shock, as well as the plasma waves and radio emissions generated by these particle. Foreshocks are a common theme in our current research program since type II solar radio bursts and the 2-3 kHz radio emissions observed by the Voyager spacecraft in the outer heliosphere are most likely generated in foreshock regions upstream of traveling shock waves, and so are qualitatively similar to radio emissions generated in Earth's foreshock for which abundant spacecraft data exist.
- Stochastic Growth Theory (SGT)
- Widespread applicability of SGT
- Theories for Radio Emissions
- Plasma Theory
- Other Progress
- Statistics of solar flares
