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[en] The results of two Antarctic rocket campaigns, primarily initiated to investigate electron precipitation stimulated by signals from the Siple-Station ground-based VLF transmitter, are presented. While the primary objective of the campaigns was not achieved, the Siple VLF transmitter facilitated a study of the wave environment in the ionosphere. Standing wave patterns in the ionosphere were observed for the first time by detectors flown aboard the Nike-Tomahawk rockets; the same detectors monitored a continuous signal from the transmitter through the neutral atmosphere and into the ionosphere, providing unique data for comparison with theoretical studies of wave propagation. The measurements of penetrating electron precipitation were interpreted in terms of a model of energetic electron precipitation from the trapped radiational belts. 52 references

No abstract available

[en] A simple model is outlined to describe electron precipitation from the population of charged particles trapped in the Earth's magnetic field; almost all of the precipitation is shown to occur in the region of the South Atlantic Anomaly (SAA). When the effect of a dawn-to-dusk electric field across the magnetosphere is included in the model, a diurnal modulation of the precipitated electron flux is predicted. Experimental evidence which supports the diurnal modulation model is described. The resulting diurnal variation in atmospheric conductivity in the SAA is shown to be such that it could account for part of the daily UT variation in the geoelectric field. The observed seasonal variation in the pattern of geoelectric field modulation is also shown to be consistent with the proposed source of the daily variation. The difficulty of altering global conductivity by intense ionization of the mesosphere is discussed. (author)

[en] A comparison is made between the measured muon energy spectrum at sea level and that predicted by four theoretical models (namely, Maeda-Cantrell (MC), constant energy (CE), Cocconi-Koester-Perkins (CKP) and scaling models). It is concluded that the scaling model agrees with the experimental data at energies less than 100 GeV, and the CKP model provides the best description of the spectrum at energies above 100 GeV

[en] Measurements of the X-ray bremsstrahlung precipitation were made during the Araks experiments. The following conclusions were deduced from the data: with several exceptions the ambient X-ray flux observed was the normal quiet background expected for the location and existing conditions. The X-ray flux at energies below 20 keV was in excess of that predicted by theory. No obvious effects of the Araks experiments were seen in the data. However, a superposed epoch analysis of the X-ray data revealed a very small amount of precipitation associated with the electron gun

No abstract available

No abstract available

[en] The absolute vertical cosmic ray muon spectrum is investigated theoretically. Models of high energy interactions (namely, Maeda-Cantrell (MC), Constant Energy (CE), Cocconi-Koester-Perkins (CKP) and Scaling Models) are used to calculate the spectrum of cosmic ray muons at sea level. A comparison is made between the measured spectrum and that predicted from each of the four theoretical models. It is concluded that the recently available measured muon differential intensities agree with the scaling model for energies less than 100 GeV and with the CKP model for energies greater than 200 GeV. The measured differential intensities (Abdel-Monem et al.) agree with scaling. (orig.)

[en] On January 4, 1978, at 1140 UT, a SuperArcas sounding rocket was launched from Siple Station, Antarctica (L = 4.2, 76⁰S, 84⁰W), during a geomagnetically disturbed period (Kp = 6--) with intense X ray and VLF chorus activity. The parachuted payload observed an intense microburst precipitation event of 10-minute duration. These data have been correlated with measurements of VLF chorus by receivers on the ground at both Siple and its magnetic conjugate point, Roberval, Quebec. Detailed one-to-one correspondence between the microbursts and the chorus was not a consistent feature of the data. Time series analysis of the data did indicate a significant correlation between the Siple X ray precipitation and the Roberval VLF waves with an arrival time delay of 0.1 +- 0.3 seconds