Structure of the magnetopause

摘要: This paper reviews present understanding of the internal structure thin boundary layer, termed magnetopause, that separates distorted geomagnetic field in magnetosphere from flow solar plasma magnetosheath. The fundamental theoretical concepts subject are introduced by considering layer exists when a cold, unmagnetized stream ions and electrons impinges normally on vacuum magnetic field. idealized model indicates how earth's is confined impact pressure wind, being terminated induced shielding currents flowing magnetopause. various idealizations approximations this model, such as assumption cold neglect interplanetary field, examined critically. presence thermal modifies so penetrate substantially deeper (∼100 km) than into Complications then arise if has component velocity parallel to occurs downstream magnetopause bounds tail. additional generates electric may destroy small-scale equilibrium result tangential drag cavity. available experimental information summarized related investigations. Although observations confirm some predictions, much detailed theory remains speculative at time.