American Institute of Physics;Melville: American Institute of Physics
摘要:
摘要： The eigenmode stability properties of three-dimensional lower-hybrid-drift-instabilities (LHDI) in a Harris current sheet with a small but finite guide magnetic field have been systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle-in-cell (PIC) simulation model with a realistic ion-to-electron mass ratio m i / m e . In contrast to the fully kinetic PIC simulation scheme, the fast electron cyclotron motion and plasma oscillations are systematically removed in the GeFi model, and hence one can employ the realistic m i / m e . The GeFi simulations are benchmarked against and show excellent agreement with both the fully kinetic PIC simulation and the analytical eigenmode theory. Our studies indicate that, for small wavenumbers, ky , along the current direction, the most unstable eigenmodes are peaked at the location where k → · B → = 0 , consistent with previous analytical and simulation studies. Here, B → is the equilibrium magnetic field and k → is the wavevector perpendicular to the nonuniformity direction. As ky increases, however, the most unstable eigenmodes are found to be peaked at k → · B → ≠ 0 . In addition, the simulation results indicate that varying m i / m e , the current sheet width, and the guide magnetic field can affect the stability of LHDI. Simulations with the varying mass ratio confirm the lower hybrid frequency and wave number scalings. 出版者： Melville: American Institute of Physics 出版日期： 2016-07-01 出處： Physics of plasmas, 2016-07, Vol.23 (7) 資源來源： AIP Journals (American Institute of Physics) 版權： Author(s) 版權： 2016 Author(s). Published by AIP Publishing. 識別號： ISSN: 1070-664X 識別號： ISSN: 1527-2419 識別號： ISSN: 1089-7674 識別號： EISSN: 1089-7674 識別號： DOI: 10.1063/1.4954830 識別號： CODEN: PHPAEN
