Accession Number : ADA296327

Title :   CRRES Observations of the Composition of the Ring-Current Ion Populations.

Corporate Author : AEROSPACE CORP EL SEGUNDO CA TECHNOLOGY OPERATIONS

Personal Author(s) : Roeder, J. L. ; Fennell, J. F. ; Chen, M. W. ; Schulz, M. ; Grande, M.

PDF Url : ADA296327

Report Date : 15 FEB 1995

Pagination or Media Count : 18

Abstract : The Magnetospheric Ion Composition Spectrometer onboard the CRRES spacecraft provided mass and charge state composition data for positive ions in the energy-per-charge range 10-425 keV/e. The CRRES data is compared to the AMPTE/CCE observations during both geomagnetically quiet and active periods. The CRRES average radial profiles of H+, He+, and He++ during quiet intervals are remarkably similar to those measured by CCE. The excess of ions measured by CRRES at L <4 compared to standard ion transport models tends to support the necessity of additional ion radial diffusion by ionospheric electric-field variations. A summary is also given of the measured storm-time variations of the major ion populations during the large storm of March 1991. The results are compared to previous observations by the AMPTE/CCE spacecraft during a large storm. The CRRES data confirm that the rapid initial recovery of the Dst magnetic index is due to a momentary change of the relative ion composition of the ring current to an oxygen-dominated state. A preliminary test of the Dessler-Parker-Sckopke relation between the ion energy and the global magnetic perturbation shows that the observed particle fluxes during the March 1991 storm could account for only 30-50% of the variation of the Dst magnetic index. (AN)

Descriptors :   *GEOMAGNETISM, *IONS, *TRAPPING(CHARGED PARTICLES), *MAGNETOSPHERE, MATHEMATICAL MODELS, IONOSPHERE, MAGNETIC FIELDS, GLOBAL, SPACECRAFT, ENERGY, ELECTRIC FIELDS, PROTONS, HYDROGEN, CHEMICAL COMPOSITION, OXYGEN, TRANSPORT PROPERTIES, PROFILES, SEASONAL VARIATIONS, CHARGE TRANSFER, PERTURBATIONS, HELIUM, SOLAR RADIATION, SPECTROMETERS, ION EXCHANGE, MAGNETIC STORMS, SYNCHRONOUS SATELLITES, ION DENSITY, PARTICLE FLUX, RADIAL FLOW, MAGNETIC MOMENTS.

Subject Categories : Atmospheric Physics
      Geomagnetism
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE