Direct detection of asymmetric increases of extraterrestrial ‘ring current’ Proton intensities in the outer radiation zone
TL;DR: In this article, the spatial distribution and temporal variations of the extraterrestrial "ring current" proton intensities near the magnetic equator during selected phases of two moderate magnetic storms on July 9 and September 8, 1966, provide direct evidence of asymmetric enhancement of these proton intensity deep in the outer radiation zone, during the early development of the latter magnetic storm.
Abstract: Measurements of the spatial distributions and temporal variations of the extraterrestrial ‘ring current’ proton intensities near the magnetic equator during selected phases of two moderate magnetic storms on July 9 and September 8, 1966, provide direct evidence of asymmetric enhancement of these proton intensities deep in the outer radiation zone, during the early development of the latter magnetic storm. Increases of these low-energy proton (5 ≲E≲50 kev) intensities in the evening-midnight quadrant of the outer radiation zone on L shells ≃3.5 to 5.0 were accompanied by a substantial polar magnetic substorm observed during similar local times. However, no increases of proton intensities at levels above those typical of the ‘quiescent ring current’ centered at L∼6.5, were yet observed near local noon, several hours later. Several implications that concern the origin and motions of this plasma during the early development phase of the magnetic storm are discussed.
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TL;DR: Magnetospheric plasma clouds equatorial observation by ATS 5 satellite, revealing plasma injection during substorms and dispersion by earth magnetic and electric fields as mentioned in this paper, revealed plasma injection in the Earth magnetic field.
Abstract: Magnetospheric plasma clouds equatorial observation by ATS 5 satellite, revealing plasma injection during substorms and dispersion by earth magnetic and electric fields
573 citations
TL;DR: Electron and proton precipitation observations in auroral, polar cap and outer radiation zones by electrostatic analyzers on earth satellite Injun 5 were carried out by as mentioned in this paper, and the results showed that the auroral and polar cap regions were relatively stable.
Abstract: Electron and proton precipitation observations in auroral, polar cap and outer radiation zones by electrostatic analyzers on earth satellite Injun 5
518 citations
TL;DR: In this paper, it was concluded that solar wind plasma can penetrate to low altitudes through the high-latitude cusp in the magnetopause, which is often referred to as the neutral point.
Abstract: Daytime high-latitude fluxes of low-energy ( 107 cm−2 ster−1 sec−1 with typical energy fluxes in the range 0.01 to 0.1 ergs cm−2 ster−1 sec−1. It is concluded that solar wind plasma can penetrate to low altitudes through the high-latitude cusp in the magnetopause, which is often referred to as the neutral point. This flux is related to a number of geophysical phenomena, including magnetospheric surface currents, daytime auroras, VLF and LF emissions, ionospheric irregularities, and geomagnetic fluctuations.
515 citations
TL;DR: Stable auroral red arcs generation at plasmapause from ion cyclotron wave turbulent dissipation of ring current proton energy as discussed by the authors, with stable red arcs generated at plasapause.
Abstract: Stable auroral red arcs generation at plasmapause from ion cyclotron wave turbulent dissipation of ring current proton energy
319 citations
TL;DR: The flow of plasma in the earth's magnetotail has been measured with an electrostatic analyzer on Vela 4B at geocentric distances of ∼18 RE, where the analyzer was kept directed radially outward along a radius vector from the earth, and so it could sense flows in the direction perpendicular to the radius vector as discussed by the authors.
Abstract: The flow of plasma in the earth's magnetotail has been measured with an electrostatic analyzer on Vela 4B at geocentric distances of ∼18 RE. The analyzer on the rotating (64-sec period) satellite measures proton energy spectra from 79 ev to 19 kev, and the plasma, flow is detected and measured by the substantial spin modulation that it often causes in the measured proton fluxes. The satellite's spin axis is kept directed radially outward along a radius vector from the earth, and so the analyzer, whose aperture is in the satellite's equatorial plane, most effectively senses flows in the direction perpendicular to the radius vector. Some results of the measurements are that (1) plasma flow speeds of several hundred km/sec are frequently measured in the plasma sheet, particularly during substorms, and these sometimes approach 1000 km/sec; however, evident flow in a given direction seldom persists for more than a few minutes; (2) these rapid substorm-related flows are usually directed generally sunward; (3) flow in the anti-sunward (tailward) direction is observed early in some substorms as the plasma sheet thins down; this may suggest the formation of a neutral line at geocentric distances <18 RE;, (4) the magnetotail is separated from the surrounding magnetosheath by a boundary layer a few thousand kilometers thick in which magnetosheath-like flow occurs but at reduced particle density and velocity; and (5) averaging of all flow measurements made in the plasma, sheet over many months does not reveal any distinct pattern of flow either sunward or anti-sunward; an average of the flows observed during periods of a few minutes of clearly evident flow, however, does reveal a flow in the general direction of the sun. It appears that the plasma sheet may often be in turbulent motion with turbulence-cell dimensions no greater than a few RE.
312 citations
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TL;DR: In this article, Ogo 3 measurements of proton and electron differential energy spectrums were used to detect charged particles of extraterrestrial ring current during geomagnetic storms, with Ogo
Abstract: Charged particles of extraterrestrial ring current during geomagnetic storms, with Ogo 3 measurements of proton and electron differential energy spectrums
411 citations
TL;DR: In this article, the motion of charged particles in a model magnetosphere is studied using the three adiabatic invariants, and particle shell geometry is determined, and drift velocities, bounce periods, and equatorial pitch angles are computed as a function of local time.
Abstract: The motion of charged particles in a model magnetosphere is studied using the three adiabatic invariants. The particle shell geometry is determined, and drift velocities, bounce periods, and equatorial pitch angles are computed as a function of local time. The following conclusions were reached: (1) Shell splitting in the outer magnetosphere becomes important beyond 5 RE (earth radii). This means that particles mirroring at different points on the same field line at noon appear spread over a region of field lines at midnight, and vice versa. (2) There are regions in the magnetosphere, where only pseudo-trapped particles can mirror, i.e. particles that will leave the magnetosphere before completing a 180° drift. (3) Longitudinal drift velocities depart considerably from the dipole values beyond 5 RE, and can be as much as 2–3 times greater on the night side than on the day side. Thus a given particle spends 2–3 times more time in the day side than in the night side. (4) After recovery from a prototype magnetic storm, particles that were in the day side during the sudden commencement will have higher energies, their shells having moved radially inward. Particles caught in the night side will have moved outward, with their energies decreased.
259 citations
01 Jan 1966
213 citations
TL;DR: Three dimensional current systems constructed semiquantitatively for polar magnetic substorms based on magnetic field distribution on earth surface were constructed in this paper for the purpose of constructing a three dimensional current system.
Abstract: Three dimensional current systems constructed semiquantitatively for polar magnetic substorms based on magnetic field distribution on earth surface
190 citations
TL;DR: In this paper, the authors suggest that the observations of localized magnetic fluctuations might be better interpreted in terms of field-aligned currents in the magnetosphere, which is inconsistent with the present theory of hydromagnetic wave propagation in the magnetic field.
Abstract: Certain satellite and terrestrial observations of transient magnetic fluctuations show a high degree of localization, while other observations are of a definite worldwide character. The worldwide fluctuations in the magnetic field are probably well explained in terms of hydromagnetic waves propagating through the magnetosphere in modes with the wave polarization current flowing perpendicular to the geomagnetic field. However, for the localized fluctuations such an interpretation is inconsistent with present theory of hydromagnetic wave propagation in the magnetosphere. We suggest that the observations of localized magnetic fluctuations might be better interpreted in terms of field-aligned currents in the magnetosphere.
181 citations