Kelvin-Helmhltz instability in the polar cusp region of the magnetosphere

摘要

Shear driven Kelvin-Helmholtz instability in the polar cusp region of magnetosphere (adjacent to ionophere) for a low β-plasma has been studied. With the help of suitable dispersion relation, the dispersion characteristic and growth rate of kelvin- Helmholtz waves (in acoustic mode waves) for different shear strengths have been calculated and the results have been used to explain ULF magnetic noise observed in the polar cusp region of the magnetosphere. Thus, the wave turbulence generated by this instability may be responsible for alternative electron pitch angle.