Biblio

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Filters: Author is Newkirk, L. L.  [Clear All Filters]
1968
Authors: Newkirk L L, and Walt M
Title: Radial Diffusion Coefficient for Electrons at 1.76 < L < 5
Abstract: Radial diffusion by nonconservation of the third adiabatic invariant of particle motion is assumed in analyzing experiments in which electrons appeared to move across field lines. Time-dependent solutions of the Fokker-Planck diffusion equation are obtained numerically and fitted to the experimental results by adjusting the diffusion coefficient. Values deduced for the diffusion coefficient vary from 1.3 × 10−5 RE²/day at L = 1.76 to 0.10 RE²/day at L = 5. In the interval 2.6 < L < 5, the coefficient varies as L10±1. Assuming a constant electron source of arbitrary magnitude at L = 6 and the above diffusion coefficients, the equatorial equilibrium distribution is calculated for electrons with energies above 1.6 Mev. The calculation yields an outer belt of electrons whose radial distr. . .
Date: 12/1968 Publisher: Journal of Geophysical Research Pages: 7231 - 7236 DOI: 10.1029/JA073i023p07231 Available at: http://onlinelibrary.wiley.com/doi/10.1029/JA073i023p07231/abstract
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Authors: Newkirk L L, and Walt M
Title: Radial Diffusion Coefficient for Electrons at Low L Values
Abstract: An empirical evaluation of the diffusion coefficient for trapped electrons diffusing across low L shells is obtained by adjusting the coefficient to account for the observed radial profile and the long-term decay rate of the trapped electron flux. The diffusion mechanism is not identified, but it is assumed that the adiabatic invariants µ and J are conserved. The average value of the coefficient for electrons > 1.6 Mev energy is found to decrease monotonically from ∼4 × 10−6 RE²/day at L = 1.16 to ∼2 × 10−7 RE²/day at L = 1.20.
Date: 02/1968 Publisher: Journal of Geophysical Research Pages: 1013 - 1017 DOI: 10.1029/JA073i003p01013 Available at: http://onlinelibrary.wiley.com/doi/10.1029/JA073i003p01013/abstract
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