16-Moment Approximation for Ion Velocity Distribution and its Application in Calculations of Incoherent Scatter Spectra

摘要: A sixteen moment approximation based on a bi-Maxwellian that contains the stress tensor and heat flow vector is applied to describe ion velocity distribution which influences incoherent scatter spectra. discussion made about effects spectra caused by different values of normalized perpendicular drift D, aspect angle between magnetic field line-of-sight direction, ratio α ion-neutral collision cyclotron frequency. Numerical results show shifting asymmetry appear parallel E × B as D increases due velocity, respectively. However, spectrum always typically double-humped Maxwellian B. The more distorted from 0° 90°, consequently no longer Maxwellian. As increases, becomes become even with large value D. It reasonable use sixteen-moment non-Maxwellian plasma characterized temperature anisotropy.