Novel Techniques for Background / Foreground Rejection in Particle Instruments

The Novel Techniques for Background / Foreground Rejection in Particle Instruments project addresses the need for signal contamination and background signal suppression for particle instrumentation (e.g. plasma instruments and mass spectrometers), a typical problem for instruments in various geomagnetic (e.g. radiations belts and strong UV illumination) and planetary environments (e.g. Jupiter and Saturn). This research will design and implement a background/foreground rejection technology using a simple thin foil and fast coincidence, with wide applicability across scientific disciplines.

Particle instruments in general such as mass spectrometers and plasma analyzers face two common problems that degrade their performance: (a) penetrating radiation through the walls of the instruments resulting in higher noise levels due to increased background signal and (b) undesirable foreground signal (e.g. ions and UV) through the aperture which degrades the useful signal. Both have the effect of reducing the useful S/N in an instrument and therefore performance. Those issues become more severe in certain environments such as the radiation belts but also in FOVs facing the solar geo – coronal light contamination. Typical mitigation techniques for background include increasing the walls of the instruments – with a heavy impact on mass, which is often impractical – or increasing thresholds in suppression. Although the use of foils and coincidence timing in plasma instrumentation is common, the foil and coincidence technique we propose has never been implemented for background/foreground suppression in this way. The proposed technique will solve this problem for future instruments in high radiation environments.