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Buck, R. M.

Publications and source records attributed to Buck, R. M..

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Chorus, energetic electrons and magnetospheric substorms

The paper investigates possible chorus generation mechanisms by means of simultaneous OGO-5 measurements of chorus, energetic (79 + or - 23 keV) electron fluxes and pitch angle distributions, and ambient magnetic fields. Further, the solar wind data during high-latitude dayside chorus events are examined. It is reported that the highly eccentric orbit had an apogee of 24 earth radii and an inclination of 30 deg to the geographic equator.

Tsurutani, B. T.↗
NASA NTRS1978

On the configuration of the magnetotail near midnight during quiet and weakly disturbed periods - State of the magnetosphere

Particle and field data are analyzed for a number of magnetically quiet days. It is shown that the magnetotail near midnight may exist for hours at a time in widely different quasi-stable configurations which, in their limit, can be characterized as being (1) fairly dipolelike to about 15 R(E), beyond which the field becomes taillike; and (2) dipolelike to only about 10 R(E), beyond which the field becomes taillike. These different states affect both the dynamics of the substorm and the evolution of the pitch angle distributions of energetic electrons in the near-earth plasma sheet past midnight. During quiet times, the plasma sheet in its azimuthal variation is at its thinnest in the region near midnight.

West, H. I., Jr.↗
NASA NTRS1973

LLL electron and proton spectrometer on NASA's Orbiting Geophysical Observatory 5

The LLL energetic electron and proton spectrometer on NASA's Orbiting Geophysical Observatory 5 (OGO-5) operated successfully from launch - March 4, 1968 - until retirement in August 1971. Data recovery during this time was about 95% of the orbit except for the last few months. The electron spectrometer used a magnetic field for electron momentum selection which served also as an electron broom for a proton range - energy telescope. The energy range was approximately 60 to 2950 keV for electrons (seven channels) and 0.10 to approximately 94 MeV for protons (seven channels). The experiment was scanned relative to the stabilized OGO-5 for obtaining directional information. Excellent data were taken throughout the magnetosphere and in the interplanetary region. Studies were carried out in the areas of equatorial pitch-angle distributions, substorm dynamics and field topology, particle spectra (time history), particle spatial distributions, and solar particle events.

West, H. I., Jr.↗
NASA NTRS1973

Electron pitch angle distributions throughout the magnetosphere as observed on Ogo 5.

A survey of the equatorial pitch angle distributions of energetic electrons is provided for all local times out to radial distances of 20 earth radii on the night side of the earth and to the magnetopause on the day side of the earth. In much of the inner magnetosphere and in the outer magnetosphere on the day side of the earth, the normal loss cone distribution prevails. The effects of drift shell splitting - i.e., the appearance of pitch angle distributions with minimums at 90 deg, called butterfly distributions - become apparent in the early afternoon magnetosphere at extended distances, and the distribution is observed in to 5.5 earth radii in the nighttime magnetosphere. Inside about 9 earth radii the pitch angle effects are quite energy-dependent. Beyond about 9 earth radii in the premidnight magnetosphere during quiet times the butterfly distribution is often observed. It is shown that these electrons cannot survive a drift to dawn without being considerably modified. The role of substorm activity in modifying these distributions is identified.

West, H. I., Jr.↗