Kinetic Alfvén Waves’ Generation in Front of the Earth’s Main Shock Wave

Abstract

We investigated the possibility of generating kinetic Alfvén waves by beams of high-speed protons in front of the Earth’s main shock wave. An analytical solution is obtained for the hose-type instability of kinetic Alfvén waves caused by the beam’s dynamic pressure. The effect of the temperature of high-speed beams and the temperature of solar wind protons on the characteristics of the generated disturbances is studied. The temperature has a significant effect on the transverse scales of disturbances: the higher the temperature of the beam protons and the lower the temperature of the surrounding plasma, the more stringent the restrictions imposed on the transverse wavelength scales. The development of instability during the propagation of beams of reflected, intermediate, and diffused protons in the region ahead of the Earth’s main shock wave is considered. The dynamics of the movement of disturbances in this region are analyzed.