HR: 0800h
AN: SH31A-1177    [Abstracts]
TI: Stochastic Waves in Space Plasmas
AU: Robinson, P A
EM: robinson@physics.usyd.edu.au
AF: University of Sydney, School of Physics University of Sydney, Sydney, NSW 2006 Australia
AU: Li, B
EM: boli@physics.usyd.edu.au
AF: University of Sydney, School of Physics University of Sydney, Sydney, NSW 2006 Australia
AU: * Cairns, I H
EM: cairns@physics.usyd.edu.au
AF: University of Sydney, School of Physics University of Sydney, Sydney, NSW 2006 Australia
AB: Burstiness of observed wave emissions and related processes in space plasmas has been addressed via various stochastic theories of wave growth. These include elementary burst theories (EBT) of solar microwave spike bursts, and stochastic growth theory (SGT) of type II and III radio bursts and other planetary and heliospheric sources. These theories are analytically unified here, the SGT and EBT regimes are elucidated, and new regimes are uncovered. It is predicted that all the subregimes have lognormal wave-intensity statistics. This is verified using published data on type III solar radio bursts, magnetospheric waves, pulsar radio emissions, and simulations, leading to data collapse onto a single theoretical curve with no free parameters. Simplified model equations for the dynamics of generalized SGT are proposed and their results are compared with quasilinear and PIC simulations, and with theory. These are the first simulations to show direct evidence of SGT. Evidence for divergence of correlation lengths as a critical point is approached is also presented, possibly pointing to existence of a self-organized critical regime.
DE: 7847 Radiation processes
DE: 7871 Waves and instabilities
DE: 6984 Waves in plasma
DE: 2159 Plasma waves and turbulence
DE: 0689 Wave propagation (4275)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting