Particle propagation effects on wave growth in a solar flux tube

Abstract

view Abstract Citations (25) References (43) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Particle Propagation Effects on Wave Growth in a Solar Flux Tube White, S. M. ; Melrose, D. B. ; Dulk, G. A. Abstract The evolution of a distribution of electrons is followed after they are injected impulsively at the top of a coronal magnetic loop, with the objective of studying the plasma instabilities which result. At early times the downgoing electrons have beamlike distributions and amplify electrostatic waves via the Cerenkov resonance; the anomalous Doppler resonance is found to be less important. Slightly later, while the electrons are still predominantly downgoing, they are unstable to cyclotron maser generation of z-mode waves with omega(p) much less than Omega, or to second harmonic x-mode waves. The energetics of these instabilities, including saturation effects and heating of the ambient plasma, are discussed. It is suggested that coalescence of two z-mode waves generated by cyclotron maser emission of the downgoing electrons may produce the observed microwave spike bursts. Publication: The Astrophysical Journal Pub Date: September 1986 DOI: 10.1086/164512 Bibcode: 1986ApJ...308..424W Keywords: Magnetohydrodynamic Stability; Particle Acceleration; Plasma Diagnostics; Solar Flares; Solar Magnetic Field; Cerenkov Radiation; Cyclotron Radiation; Electron Distribution; Solar Physics; PARTICLE ACCELERATION; SUN: FLARES; SUN: MAGNETIC FIELDS full text sources ADS |