Evaluation of Magnetospheric Internal Magnetic Field models and Existing Software

Abstract

In preparation for analysis of the CRRES databases (to be taken from 1990 to 1995) and, in particular, for an updated static radiation belt model, a comparison has been made of four magnetospheric internal magnetic field models. Since there is interest in radiation belt models out to geosynchronous altitudes, it will be necessary to consider the external magnetic field models as well, but for now just the internal models will be discussed. The four models reviewed here are Barraclough, MAGSAT, IGRF 1985, and Cain. Each of these has an optimal time period associated with it: Barraclough 1975, MAGSAT 1980, IGRF 1985, and Cain 1990. In the subsequent sections of this report, the derviations of these models will be summarized. They are all based on these spherical harmonic expansion of the magnetic field's scalar potential. The data used to determine each set of coefficients will be briefly discussed. Then the models will be evaluated by comparing the magnetic field and L-shell values obtained from each of the models. Finally, various computer codes which use these models to evaluate the field and L-shell, will be compared and evaluated in terms of their performance (i.e. accuracy and speed). A primary concern for radiation belt models is reduction of the number of binning parameters by using B-L coordinates. Keywords: Spherical harmonic models, Dipole, Moments.

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Document Details

Document Type
Technical Report
Publication Date
Jan 31, 1990
Accession Number
ADA221816

Entities

People

  • C. E. Jordon
  • J. N. Bass

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Accuracy
  • Air Force
  • Algorithms
  • Altitude
  • Computational Science
  • Data Sets
  • Differential Equations
  • Digital Data
  • Dipole Moments
  • Equations
  • Grids
  • High Latitudes
  • Interpolation
  • Magnetic Fields
  • Magnetic Moments
  • Reliability
  • Standards

Readers

  • Computational Modeling and Simulation
  • Space Exploration and Orbital Mechanics.