MSSL PRD Case for Support: Solar Wind Plasma Analyser/Electron Analyser System for Solar Orbiter

One of the key measurement goals for the ESA Solar Orbiter mission is to characterise the particle populations found in the solar wind, particularly in the unexplored 'inner heliosphere' region close to the Sun. In doing so, we will be able to obtain clues to both the physical processes that occur between plasmas and magnetic fields in the solar wind, to examine the effect of solar wind structures, such as coronal mass ejections, as they propagate away from the Sun, and also to make the important link between the solar wind and the activity in the Solar atmosphere in order to understand how the solar wind and the structures within it are formed. UCl/MSSL is part of an international consortium which will propose to build the instruments that will measure the charged particle populations in the solar wind. In particular, MSSL will provide the 2 sensors that are required to make a complete measurement of the electron populations within the solar wind. Since the Solar Orbiter mission will go closer to the Sun than any previous mission, there are a number of technical challenges that must be overcome in order to achieve the required measurements and gain the required science return. We have built a prototype sensor which is under test within the MSSL thermal vacuum chambers. Further testing and design work is required to tune the sensors to maximise their effectiveness in the inner heliospheric environment. In addition MSSL is required to collaborate with ESA in order to ensure that the interfaces between our sensors and the spacecraft are well defined and appropriate. The purpose of the tasks proposed here are to carry out these design and trade-off studies in order to maximise the chances of scientific success once the instrument is built and the mission launched.