The integrated miniaturized electrostatic analyzer: A space plasma environment sensor.

The integrated Miniaturized Electrostatic Analyzer (iMESA) was a satellite-based ionospheric sensor that operated on NASA's Space Test Program Satellite (STPSat-3) from December 2013 to July 2019. The instrument's scientific objective was to (1) measure the plasma density in low Earth orbit, (2) measure the plasma temperature in low Earth orbit, and (3) quantify the spacecraft potential with respect to the ambient plasma potential in the ionosphere. iMESA sampled the ionosphere every 10 s by measuring the ion current density through the ESA as a result of the motion of the spacecraft through the plasma.

A laminated energetic electrostatic analyzer for 0-5 keV charged particles.

A compact electrostatic energy bandpass filter based on a laminated analyzer design has been developed to measure charged particle fluxes at energies ranging from 0 to 5 keV. The sensor head has been successfully tested against a low energy magnetically filtered plasma source and an ion beam source capable of producing energetic ions in the range of 100-1250 eV. Additionally, the instrument has demonstrated the ability to accurately measure negative spacecraft frame charging using a low Earth orbit plasma simulator.

Screens versus microarrays for ruggedized retarding potential analyzers.

An array of highly miniaturized electrostatic lenses is shown to be a viable replacement for meshes or screens in a retarding potential analyzer (RPA) where mechanical ruggedness or the ability to intercept large currents of energetic particles is desirable. Data from a prototype device are presented cross-calibrated with a traditional planar RPA indicating how the so-called microarray configuration avoids energy-dependent transparency (either reduced or enhanced) associated with meshes or screens while providing accurate energy analysis with reasonable energy resolution. In contrast, another ruggedized configuration employing a screen is presented, showing the severity of energy-dependent enhanced transparency, verified by numerical simulation.