Ring current ion interaction with micropulsations

摘要: The interaction between ring current ions and Pc 5 micropulsations has been studied numerically using a test particle code. Due to the convection potential, which increases during geomagnetic storms, the low energy (≲ 10 keV) ions injected at midnight from the magnetotail cannot complete a drift path around the earth and are lost to the dayside magnetopause. The intermediate energy O+ ions (tens of keV) interact with Pc5 micropulsations via a drift-bounce resonance. The resonant interaction leads to energy loss or gain for the particles, depending on their guiding center position with respect to the phase of the micropulsations. Once the energy drops below that required to overcome the convection potential, the particle will be lost to the magnetopause. H+ ions satisfy the drift-bounce resonance condition at higher energies, where the convection potential is negligible, and at lower energies where the convection …