High and low frequency instabilities driven by a single electron beam in two-electron temperature space plasmas

Journal Article · Sun Dec 15 04:00:00 EST 2013 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4851995· OSTI ID:22218325

Mbuli, L. N. ^[1]; Maharaj, S. K. ^[1]; Bharuthram, R. ^[2]

---

1. South African National Space Agency (SANSA) Space Science, P.O. Box 32, Hermanus 7200, Republic of South Africa (South Africa)
2. University of the Western Cape, Robert Sobukwe Road, Bellville 7535, Republic of South Africa (South Africa)

In an attempt to understand the excitation mechanisms of broadband electrostatic noise, beam-generated electrostatic instabilities are investigated using kinetic theory in a four-component magnetised plasma model composed of beam electrons (magnetic field-aligned), background hot and cool electrons and ions. All species are fully magnetised and considered to be Maxwellian. The dependence of the instability growth rates and real frequencies on various plasma parameters such as beam speed, particle densities and temperatures, magnetic field strength, wave propagation angle, and temperature anisotropy of the beam are examined. In this study we have found that the electron-acoustic, electron beam-resonant and ion-acoustic instabilities are excited. Our studies have focused on three velocity regimes, namely, the low (v{sub dbz}2 C{sub h}) regimes, where v{sub dbz} (C{sub h}) is the electron beam drift speed (thermal speed of the hot electrons). Plasma parameters from satellite measurements are used where applicable to provide realistic predictions.

• OSTI ID: 22218325
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 12 Vol. 20; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ELECTROMAGNETIC RADIATION
ELECTRON BEAMS
ELECTRON TEMPERATURE
ELECTRONS
EXCITATION
INSTABILITY GROWTH RATES
ION TEMPERATURE
MAGNETIC FIELDS
PLASMA DENSITY
PLASMA INSTABILITY
WAVE PROPAGATION