Read Full Article (file size: 323972 bytes)    Cited by

GEOPHYSICAL RESEARCH LETTERS, VOL. 29, NO. 24, 2205, doi:10.1029/2002GL015963, 2002

Field line dependence of magnetospheric electron density

R. E. Denton

Department of Physics and Astronomy, Dartmouth College, Hanover, NH, USA

J. Goldstein

Department of Physics and Astronomy, Rice University, Houston, TX, USA

J. D. Menietti

Department of Physics and Astronomy, University of Iowa, Iowa City, IA, USA

Abstract

Observations of the electron density n_e based on measurement of the upper hybrid resonance frequency by the Polar spacecraft Plasma Wave Instrument (PWI) are available for March, 1996 to September, 1997, during which time the Polar orbit sampled all MLT values three times. Using this data set, we assume a power law form for the electron density dependence along field lines n_e = n_e0 (R_max/R)^α, where n_e0 is the equatorial electron density and R_max ≈ LR_E is the maximum geocentric radius R to any point on the field line, and model the statistical average of α as α_model = 8.0 − 3.0 log₁₀n_e0 + 0.28 (log₁₀n_e0)² − 0.43(R_max/R_E) for all categories of plasma (plasmasphere and plasmatrough), with an average error of 0.65. The data set on which this result is based is limited to 2.5R_E ≤ R_max ≤ 8.5R_E, 2R_E ≤ R ≤ R_max, and 2 ≤ n_e0 ≤ 1500 cm⁻³. There is no remaining dependence of the average α – α_model on MLT or Kp.

Published 27 December 2002.

Index Terms: 2768 Magnetospheric Physics: Plasmasphere; 2730 Magnetospheric Physics: Magnetosphere—inner; 2740 Magnetospheric Physics: Magnetospheric configuration and dynamics; 2794 Magnetospheric Physics: Instruments and techniques.

Read Full Article (file size: 323972 bytes)    Cited by

Citation: Denton, R. E., J. Goldstein, and J. D. Menietti (2002), Field line dependence of magnetospheric electron density, Geophys. Res. Lett., 29(24), 2205, doi:10.1029/2002GL015963.

Copyright 2002 by the American Geophysical Union.