perhaps one earth radius inside the plasmasphere with the rest outside. Nonetheless, there could be substantial overlap between the ring currents, especially during storm times when the plasmasphere is eroded and the natural ring current driven in by convection electric fields. The argon ring current can make a substantial contribution to the plasmaspheric pressure and hence to the currents which flow there (both across and along B); this will significantly stiffen the plasmasphere to deformations associated with enhanced storm-time convection electric fields and diminish the strength of electrostatic radial diffusion. The result may be (other things being unchanged) a buildup of ring-current particles and inhibition of inward transport of higher-energy particles. In summary, SPS injection of Ar+ and heating of the plasmasphere and ionosphere system necessarily imply substantial modification of the composition and density of the thermal and ring current particles of the magnetosphere. The increase of thermal heavy ion populations is likely to suppress ion cyclotron plasma turbulence, which is primarily responsible for scattering loss of radiation belt relativistic electrons. On the other hand, addition of thermal plasma would increase the loss rate of ring current electrons, thus modifying the auroral process during magnetic storms. F. Radiation Belt Modification The radiation belts consist of energetic electrons and ion (E [[spi:math]] 100 keV) trapped in two toroidal shells in the magnetosphere (Figure A1) earthward of GEO. The relativistic ion component probably originate from the decay of solar neutrons and from the effects of heavy cosmic-ray particles. The heavy particles, also known as HZE (for high atomic number and energy) particles, are the most penetrating and are hazardous to humans and to space-borne equip52
RkJQdWJsaXNoZXIy MTU5NjU0Mg==