Anisotropic-ion-beam-plasma interaction: drift parallel to magnetic field

In a plasma in which both the ions and electrons are magnetized, low-frequency electrostatic instabilities driven by an anisotropic ion beam drifting parallel to the external magnetic field are investigated. The instability spectrum is found to be dominated by the ion-acoustic and ion-ion two-stream instabilities. Detailed comparisons are made with the isotropic case. (author)