Influence of wave-particle interactions on solar-flare dynamics

Thesis/Dissertation · Mon Jan 01 04:00:00 EST 1990

OSTI ID:5224264

McKean, M E

Particle simulations are used to investigate the transport of energy across magnetic field lines by electron cyclotron maser radiation, and the conduction of energy along field lines by expanding electron populations heated during the impulsive phase. Results are applied to models for the emission of microwave spike bursts and Earth's Auroral Kilometric Radiation (AKR), both of which are probably maser emission, and for hard and soft x-ray emission. In the first section, the propagation of maser radiation through an opaque coronal absorption layer is examined, and the sources of the frequency fine structure observed in maser emission are sought. It is found that maser radiation can heat the absorption layer plasma to soft x-ray emitting temperatures. A few percent of the maser radiation can escape the absorption layer by nonlinear reemission processes. In the second section, the expansion of hot electrons is studied in regions of both uniform and nonuniform density. For uniform densities, contrary to the expectations of the thermal model for hard x-ray emission, no conduction front forms as the electrons expand and hence the heated region cools rapidly. For nonuniform densities, as electrons expand an ambipolar electric field forms that slows the expansion and accelerates ions outward. Two soft x-ray emission models are simulated.

• Research Organization: Colorado Univ., Boulder, CO (United States)
• OSTI ID: 5224264
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAE
DYNAMICS
ELECTROMAGNETIC RADIATION
EMISSION
ENERGY TRANSFER
IONIZING RADIATIONS
MECHANICS
MICROWAVE RADIATION
RADIATIONS
SOLAR ACTIVITY
SOLAR FLARES
X RADIATION