This thesis concentrates on laboratory measurements of the Electron Drift Instrument (EDI), focussing primarily on the EDI optics of the system. The EDI is a device used on spacecraft to measure electric fields by emitting an electron beam and measuring the E X B drift of the returning electrons after one gyration. This drift velocity is determined using two electron beams directed perpendicular to the magnetic field returning to be detected by the spacecraft. The EDI will be used on the Magnetospheric Multi-Scale Mission. The EDI optic's testing process takes measurements of the optics response to a uni-directional electron beam. These measurements are used to verify the response of the EDI's optics and to allow for the optimization of the desired optics state via simulation. The optics state tables were created in simulations and we are using these measurements to confirm their accuracy. The setup consisted of an apparatus made up of the EDI's optics and sensor electronics was secured to the two axis gear arm inside a vacuum chamber. An electron beam was projected at the apparatus which then used the EDI optics to focus the beam into the micro-controller plates and onto the circular 32 pad annular ring that makes up the sensor. The concentration of counts per pad over an interval of 1ms were averaged over 25 samples and plotted in MATLAB. The results of the measurements plotted agreed well with the simulations, providing confidence in the EDI instrument.

The Magnetospheric Multiscale mission led by NASA has been designed to study the micro-physics of Magnetic Reconnection in Earth's magnetosphere by using four identical spacecrafts with instruments with high temporal and spatial resolutions. Among these instruments are the Dual Ion Spectrometers (DIS) engineered to measure the 3D distribution of ion flux in space. The detector assembly of the DIS consists of Micro-Channel Plates (MCP) mounted in Chevron configuration. Centre d'Etude Spatiale des Rayonnements (CESR), Toulouse is responsible for the provision and testing of all fifty MCP pairs for this mission. The goal of the work was to participate in the testing and characterization of the first prototype of the MCPs. It was achieved by understanding the working and characteristics of the MCPs in general and getting familiar with the detector assembly of the DIS i.e. the MCP pair and the detector circuit board in particular. To perform the testing, it was necessary to understand the testing system as well. These topics are described in this report along with the testing procedure and the data analysis. The testing procedure was developed eventually after facing several problems during the testing. MCP pair characteristics like pulse height distributions, gain, resistance and the MCP operating voltages for the mission were determined on analyzing the data. Crosstalk was found in the circuit board of the detector assembly and has also been discussed. / Validerat; 20101217 (root)