The Cassini radio and plasma wave investigation is designed to study radio emissions, plasma waves, thermal plasma, and dust in the vicinity of Saturn. Three nearly orthogonal electric field antennas are used to detect electric fields over a frequency range from 1 Hz to 16 MHz, and three orthogonal search coil magnetic antennas are used to detect magnetic fields over a frequency range from 1 Hz to 12 kHz. A Langmuir probe is used to measure the electron density and temperature. Signals from the electric and magnetic antennas are processed by five receiver systems: a high frequency receiver that covers the frequency range from 3.5 kHz to 16 MHz, a medium frequency receiver that covers the frequency range from 24 Hz to 12 kHz, a low frequency receiver that covers the frequency range from 1 Hz to 26 Hz, a five-channel waveform receiver that covers the frequency range from 1 Hz to 2.5 kHz in two bands, 1 Hz to 26 Hz and 3 Hz to 2.5 kHz, and a wideband receiver that has two frequency bands, 60 Hz to 10.5 kHz and 800 Hz to 75 kHz. In addition, a sounder transmitter can be used to stimulate plasma resonances over a frequency range from 3.6 kHz to 115.2 kHz. Fluxes of micron-sized dust particles can be counted and approximate masses of the dust particles can be determined using the same techniques as Voyager. Compared to Voyagers 1 and 2, which are the only spacecraft that have made radio and plasma wave measurements in the vicinity of Saturn, the Cassini radio and plasma wave instrument has several new capabilities. These include (1) greatly improved sensitivity and dynamic range, (2) the ability to perform direction-finding measurements of remotely generated radio emissions and wave normal measurements of plasma waves, (3) both active and passive measurements of plasma resonances in order to give precise measurements of the local electron density, and (4) Langmuir probe measurements of the local electron density and temperature. With these new capabilities, it will be possible to perform a broad range of studies of radio emissions, wave-particle interactions, thermal plasmas and dust in the vicinity of Saturn.

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We present simultaneous measurements at high temporal resolution of flux transfer events (FTEs) earthward of the magnetopause using four instruments on the Active Magnetospheric Particle Tracer Explorers (AMPTE) UKS spacecraft. The seven events in our study are distributed in local time from early dawn to midafternoon over a GSM latitude range of ∼40°, from 24°N to 17°S. A multilayered structure is revealed with systematic behavior in fields and charged particle populations. The plasma pressure varies in anticorrelation with the field pressure, the total pressure in general exceeding that of the surrounding medium. While it is not the prime concern of this paper to discuss the validity of models proposed for FTEs, the new, detailed experimental results it contains make it clear that the Russell‐Elphic [1978] model needs, at the very least, more detailed development.

Abstract.Highly-coherent waves in the frequency range 1-15 Hz are usually observed upstream of the ramp of supercritical quasi-perpendicular shocks. A few models have been proposed to explain their origin. In the present paper the wave vectors of these waves are determined using AMPTE UKS and AMPTE IRM data in order to differentiate between theoretical models.