Measurements from electrostatic analyzers aboard the polar-orbiting S3-3 satellite have been tabulated to form a synoptic picture of the occurrence of upgoing 90eV to 3.9keV auroral ions. In this survey, a distinction is made between ion distributions having peak fluxes along B (beams) and those exhibiting flux maxima that are not field-aligned (conics). It is shown that both beams and conics are common auroral phenomena, whose frequencies of occurrence in latitude, local time, and altitude have a marked dependence on magnetic activity. During quiet conditions (Kp • 3) conical ion distributions are observed with constant frequency in altitude above 1000 km and appear to be associated with the daytime polar cusp region. In contrast, quiet time ion beams have a maximum occurrence frequency in the premidnight sector. Ion beams are observed primarily above 5000 km, with a frequency increasing with altitude up to the satellite apogee at 8000 km. During disturbed times, ion beams are a persistent phenomenon, mainly confined to the dusk sector, while conical distributions are observed uniformly in local time with a frequency that increases steadily in altitude. The results of this study, which are shown to be consistent with previous surveys of upward flowing ions if no distinction is made between conical and field-aligned distributions, provide information relating to auroral ion acceleration processes.

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Charged particle data taken by the S3‐3 satellite, reported by Mizera and Fennell (1977), are presented as contours of the velocity distribution function on a velocity‐space diagram. This report focuses on the analytical technique used to interpret the particle data. Details of features exhibited by the electron and ion data in the velocity‐space representations are discussed in terms of a simple electrostatic acceleration model. The observed particle populations are separated in velocity‐space by recognizable demarcations calculated from the conservation laws in accordance with Liouville's theorem.

Ion pitch angle distributions, measured in a near‐synchronous orbit, are predominantly field aligned at low energies and predominantly peaked perpendicular to the magnetic field at higher energies. The transition from field‐aligned fluxes to fluxes peaked predominantly perpendicular to the magnetic field occurs over a very narrow energy range. These ion distributions have been observed at all local times between 5.3 and 7.8 RE. This transition energy correlates with the deep minimum observed in the ion spectra. There is no apparent correlation between the ion transition energy and magnetic local time, L, Kp, or Dst. However, the transition energy does respond to observed particle injections. The transition energy decreases prior to injection, increases abruptly at injection by as much as 10–20 keV, and then decreases slowly after injection. Fresh low‐energy ions are supplied at injection and decrease in intensity over several hours to instrument threshold level. Ion drift trajectory calculations indicate that the low‐energy component below the transition energy drifts in from the nightside plasma sheet via local morning to the dayside. The high‐energy component, above the transition energy, arrives on the dayside via local evening.

Omnidirectional proton intensities (E ≈ 9‐310 MeV) have been measured in seven energy channels by means of instruments on board the satellite OV1‐19 (1969‐25C). Unidirectional spectra representative of the time interval March–November 1969 (a period near solar maximum) have been constructed from the data by standard methods. The results enable one to construct the distribution functionf(M, L) at vanishing second invariant J for 1.18 ≤ L ≤ 2. The profiles of f(M, L) thus obtained are manipulated by a new variational method to yield normalization parameters for the radial diffusion coefficients DLL(m) and DLL(e), caused, respectively, by magnetic and electrostatic impulses of magnetospheric extent. One typically obtains DLL ∼ [7 × 10−9 + 1 × 10−10 × (γM0/M)²]L10 day−1 as the best two‐parameter fit to DLL ≡ DLL(m) + DLL(e), where M0 ≡ 1 GeV/G and γ is the ratio of relativistic mass (m) to rest mass (m0).