HR: 1340h
AN: SH33B-0379 [Abstracts]
TI: Multiscale simulations of type III solar radio emission via beam-driven Langmuir waves
AU: Li, B
EM: boli@physics.usyd.edu.au
AF: School of Physics, University of Sydney, Parramatta Rd, Camperdown, Sydney, NSW 2006
Australia
AU: Robinson, P
SH33B-0379
AF: School of Physics, University of Sydney, Parramatta Rd, Camperdown, Sydney, NSW 2006
Australia
AU: * Cairns, I
SH33B-0379
AF: School of Physics, University of Sydney, Parramatta Rd, Camperdown, Sydney, NSW 2006
Australia
AB:
For most type III bursts, it is usual to invoke plasma emission mechanism to generate
the observed levels of emission near the plasma frequency and its second harmonic.
This mechanism consists of a sequence of steps:
(i) the energetic electron beam generates primary Langmuir waves by a beam instability;
(ii) the primary Langmuir waves undergo electrostatic decays and generate
product Langmuir waves and ion-acoustic waves;
(iv) the product ion-acoustic waves stimulate the primary Langmuir waves to produce
electromagnetic emission at the fundamental frequency;
and (iv) the nearly oppositely-directed Langmuir waves coalesce and
generate electromagnetic emission at the second harmonic
of the electron plasma frequency.
Here we present the first multiscale simulations of type III solar radio emission
driven by electron beams, including the dynamics of the beams
and generation of Langmuir and ion-acoustic waves, and electromagnetic radiation.
The evolution profiles of the emissions in coordinate and phase space are
explored for illustrative parameters of type III radio bursts
in the corona and at 1 AU.
The effects of density inhomogeneities on emission processes are included,
and the evolution of the beam-Langmuir wave system to
a stochastic growth state is demonstrated.
DE: 7534 Radio emissions
DE: 7829 Kinetic waves and instabilities
DE: 7857 Stochastic phenomena (3235, 3265, 4475)
DE: 7867 Wave/particle interactions (2483, 6984)
DE: 7868 Wave/wave interactions
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005