Time‐Dependent Sensitivity of a Sensor Based on a Top‐Hat Electrostatic Analyzer and Microchannel Plate Detector

Abstract Some space plasma parameters, such as electron density, can be obtained from the plasma wave spectrum, such as plasma oscillations, and from the phase space density of the electrons. Two critical advantages of having such multiple independent measurements of the same quantity are that they provide a validation of the measurements and a cross‐calibration between techniques. The electron phase space density is typically obtained using an energy analyzer and a detector, whose detection efficiency usually changes over time. Here, we use the Jovian Auroral Distribution Experiment (JADE) electron sensors to characterize the time dependence of the sensors' sensitivity. The derived sensitivity enables consistency of the derived fluxes from the different sensors. It enables the combining of data sets from independent measurements and thus extends the knowledge of many measured quantities. The derived detection efficiency is a physics‐based, semi‐empirical model that can be applied to other detectors (microchannel plates and channel electron multipliers).