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Measurements of stray antenna capacitance in the STEREO/WAVES instrument: Comparison of the measured voltage spectrum with an antenna electron shot noise model

Eastwood, J. P.; Maksimovic, M.; Bale, S. D. +6 more

One of the most accurate techniques for in situ measuring the electron density and temperature in space plasmas is the quasi-thermal noise spectroscopy, which uses the voltage fluctuation spectrum on an electric antenna. This technique has been used successfully on the WIND and ULYSSES spacecraft; however, on STEREO this technique may only work in…

Observation of long-duration gyroharmonic resonances: A refutation of the short-duration explanation for interpreting the anomalous URAP sounder spectra observed in the Io torus

Canu, Patrick

The resonance spectra collected by the Ulysses Unified Radio and Plasma Wave relaxation sounder in the Jovian magnetosphere at the outskirts of the Io torus exhibit significant differences from those gathered from earthbound spacecraft. The main deviation is the lack of resonances at the harmonics of the electron gyrofrequency. Extrapolated from s…

Measurement of the propagation speed of plasma inhomogeneities in the solar corona using an uplink/downlink cross-correlation method

Pätzold, Martin; Bird, Michael K.; Plettemeier, Dirk +3 more

Radio sounding investigations were performed over a period of about 30 days during the 1991 solar occultation of the Ulysses spacecraft (August and September 1991). Dual-frequency Doppler and ranging measurements were obtained using the NASA Deep Space Network. For this experiment the radio ray path from Ulysses to Earth moved essentially parallel…

An explanation for the absence of sounder-stimulated gyroharmonic resonances in the Io plasma torus by the Ulysses relaxation sounder

Stone, R. G.; Fainberg, J.; Benson, R. F. +2 more

Plasma resonances were excited by the relaxation-sounder component of the unified radio and plasma wave instrument (URAP) during the Ulysses encounter with Jupiter's Io plasma torus. The observed resonant spectra were quite different than expected, based on earlier published observations from topside sounders in the terrestrial ionosphere and rela…