The ten invited papers presented at the Symposium on The Role of Ion Composition in Understanding Magnetospheric Processes, which was held on 11 August 1981 in Edinburgh, Scotland, have formed the principal basis for this book. The symposium was a part of the Fourth Scientific Assembly of the International Association of Geomagnetism and Aeronomy and was convened by the Division III Working Group on Composition of Hot Magnetospheric Plasma under the co chairmanship of Dr. Gerhard Haerendel and myself. The symposium papers have been expanded and are supplemented in this book by several additional papers to provide a more comprehensive topical review and a current status report on experimental and theoretical research that relate to our present understanding of the energetic ion composition in Earth's magnetosphere. Thus, the papers include new results as well as a review of published results, with rather extensive reference lists, in the hope that this collection will be useful both for information on current research activities as well as a somewhat lasting topical resource for the space science community.

Inhalt
Principles of Magnetospheric Ion Composition.- Ion Acceleration Mechanisms in the Auroral Regions: General Principles.- Transverse Acceleration of Ions on Auroral Field Lines.- What Magnetospheric Workers Should Know about Solar Wind Composition.- Composition and Characteristics of the Polar Wind.- Low-Altitude Energetic Ion Composition Observations.- Hot Plasma Composition Results from the S3-3 Spacecraft.- The Composition of Thermal and Hot Ions Observed by the GEOS-1 and -2 Spacecraft.- Hot Plasma Composition Results from the ISEE-1 Spacecraft.- Observations of Low-Energy Plasma Composition from the ISEE-1 and SCATHA Satellites.- Hot Plasma Composition Results from the SCATHA Spacecraft.- Composition of the Hot Magnetospheric Plasma as Observed with the PROGNOZ-7 Satellite.- Initial Hot Plasma Composition Results from the Dynamics Explorer.- Experimental Determination of Geomagnetically Trapped Energetic Heavy Ion Fluxes.- Atmospheric and Ionospheric Effects of Precipitated Energetic O+ Ions.