Premium
Temperature Dependence of Plasmaspheric Ion Composition
Author(s) -
Goldstein J.,
Gallagher D.,
Craven P. D.,
Comfort R. H.,
Genestreti K. J.,
Mouikis C.,
Spence H.,
Kurth W.,
Wygant J.,
Skoug R. M.,
Larsen B. A.,
D. Reeves G.,
De Pascuale S.
Publication year - 2019
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
eISSN - 2169-9402
pISSN - 2169-9380
DOI - 10.1029/2019ja026822
Subject(s) - ion , van allen probes , atomic physics , spacecraft , mass spectrometry , chemistry , physics , plasma , van allen radiation belt , nuclear physics , magnetosphere , astronomy , organic chemistry , chromatography
We analyze a database of Dynamics Explorer‐1 (DE‐1) Retarding Ion Mass Spectrometer densities and temperatures to yield the first explicit measure of how cold ion concentration depends on temperature. We find that cold H + and He + concentrations have very weak dependence on temperature, but cold O + ion concentration increases steeply as these ions become warmer. We demonstrate how this result can aid in analyzing composition data from other satellites without spacecraft potential mitigation, by applying the result to an example using data from the Van Allen Probes mission. Measurement of light ion concentrations above 1 electron volt (eV) are a reasonable proxy for the concentrations of colder (eV) ions. Warmer O + ion concentrations may be extrapolated to colder temperatures using our fit to the statistical distribution versus temperature.