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Electron intensities and substorm drift effects in outer radiation belt using two satellite technique
Solar burst time profiles and dynamic spectra for calculating theoretical values for Type 3 burst characteristics
Performance of thrust augmented Thor Agena launch vehicle
Performance accuracy of pulse code modulation telemetry data information system for scientific satellites
Direct measurement of thermal ion distributions in magnetosphere to determine position and structure of plasmapause
Satellite multispectral photometry data in airglow bands correlated with cloud characteristics and surface albedo variations
Ionospheric electric and electromagnetic waves broadband characteristics, investigating auroral hiss and LHR noise
The gas-surface interaction effects observed by the quadrupole mass spectrometer are described, and the technique developed to account for them in determining ambient neutral densities is summarized. The total ion current and the ion currents for ions with molecular weights 2, 4, 16, 28, and 32 are sampled for 1.125 sec once every 9.216 sec, for 258 sec out of a 368 sec cycle. An equation is given for the number density of any constituent in the ion source region, and source density data are discussed. The mass 28 background gas is considered to be CO rather than N2, and a CO model is developed. A quasi-equilibrium model of the atomic oxygen interactions is constructed, and a set of surface parameters is determined which provides a reasonable fit to the mass 16 and 32 source densities consistent with the predicted ambient atomic oxygen.
A description is given of the fabrication, installation, and operation of the microphone density gage instrument. An analysis of the resulting problems and minor failures is also given. The approach to the data analysis is discussed and the significant results obtained are presented.
Description of the first experimental determination of the wave-normal vector of proton whistlers in the ionosphere. Between the crossover frequency and the proton gyrofrequency, both right-hand and left-hand modes of propagation can occur for upgoing waves. Theoretically, the amount of energy in the respective modes depends on theta, the angle between the wave normal and the magnetic field. For proton whistlers with only left-hand mode energy between the crossover and proton gyrofrequency, theta ranged from 36 to 51 deg. For proton whistlers with strong right-hand and left-hand mode signals, theta ranged from 24 to 29 deg. The result is in good agreement with Wang's (1971) collisionless mode-coupling model. The angle between the wave normal and the vertical is found to increase with increasing altitude.
Determination of the origin of auroral hiss by comparing the records of a vlf experiment (0.3 to 18 kHz) with simultaneous data obtained by an auroral-particle experiment having detectors for precipitating electrons at 0.7, 2.3, and 7.3 keV. It is found that, on the dayside of the earth, the occurrence of vlf hiss correlates well with precipitation events at 0.7 keV, but in general very poorly with activity in the higher-energy channels. Exact correlation between variations in vlf hiss intensity and in electron fluxes is rare even at 0.7 keV. In addition, vlf hiss tends to be observed over a somewhat larger spatial region than precipitating 0.7-keV electrons. It is concluded that, on the dayside, auroral hiss is generated by soft (E less than 1 keV) 'cusp region' electrons and that the lack of detailed correlation between the two phenomena is caused by propagation effects as the hiss travels downward and spreads from the generation region.
Comparison of plasmapause positions with Pi micropulsation events observed at College (L 5.4) or at Sodankyla (L 5.1), showing that in almost all cases the plasmapause was inside the field line of the observing site when the Pi event was recorded. Strong Pi events were seen at Nurmijaarvi (L 3.4) only when Kp was very high, when the plasmapause would be expected to be inside L 3.4. When Pi events and structure Pc 1 events were observed nearly simultaneously, the Pi activity was always more prominent at the poleward site. A demarcation line seems to exist, separating the Pi and structured Pc 1 source regions. This line may be the plasmapause, with structured Pc 1 inside and Pi outside.
Since July 1967, knowledge concerning the distributions of picogram size particulate matter in selenocentric space has been obtained from the Lunar Explorer 35 dust particle experiment. For almost 40% of the time, the mean sporadic cumulative flux is quite similar to the flux in interplanetary space. However, there are fluctuations of an order of magnitude during major meteor showers. The coincident increase of the flux in selenocentric space during the shower periods has been observed for the fourth year. The 100-picogram sensor does not show an increase during shower times, indicating a mass threshold of less than 100 picograms for particles with velocities equal to or greater than lunar escape velocity. The flux values from Lunar Explorer 35 are compared to other long-lifetime measurements in selenocentric, cislunar and interplanetary space with excellent agreement for masses less than one nanogram.
The data processing and analysis performed for the charged particle experiment are summarized, and the principal scientific results obtained from the analysis are reported. A bibliography is included of conference reports, and publications based on these results is included.
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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.
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