ASPOC & PICAM IWF/ÖAW GRAZ1 Main task  Development of hard- and software for flight instruments Main research topics 1.Magnetospheric MultiScale  Development of the Active Spacecraft Potential Control (ASPOC)  PI-ship (R. Nakamura) 2.BepiColombo  Development of the Planetary Ion CAMera (PICAM)  Sensor PI-ship (H. Lichtenegger) MMS stacked for vibration test

Lead: Harald Jeszenszky & Gunter Laky Members  Staff: G. Fremuth, F. Giner, C. Kürbisch, M. Leichtfried, G. Prattes, R. Wallner Cooperation within IWF  Magnetotail Physics (Nakamura et al.): MMS mission planning  SW-Atmosphere (Lammer et al.): BepiColombo mission planning  Space magnetometers (Magnes et al.): Magnetic cleanliness, parts  Exchange of know-how with all instrument developers Key external collaboration Italy: IAPS; Germany: MPS; France: LATMOS-SA; Hungary: Wigner RCP RMKI; Ireland: University of Ireland at Maynooth; Austria: FOTEC; USA: Southwest Research Institute Who are we? IWF/ÖAW GRAZ2

Operating principle  Caused by the equilibrium of various charging currents on a body embedded in plasma, the S/C gets positively charged and severely disturbs measurements of the plasma environment.  ASPOC emits a beam of positive indium ions at variable currents, keeping the S/C potential <+4 V. This ensures effective and complete acquisition of the ambient plasma distribution functions. Instrument components  Electronics box (DPU, DC- and HV-converter board)  Two emitter modules, each containing 2 emitters  External harness between box and modules (LV, HV)  A system of dry nitrogen purge lines  Ion emitter consists of emitter capillary, indium reservoir and a heater element ASPOC: Active S/C Potential Control IWF/ÖAW GRAZ3 Emitter module cross-section

 Spacecraft potential is controlled by two ASPOC instruments (~6 keV, ~10-50 µA), pointing in antiparallel directions for achieving maximum possible symmetry  Supports high-quality plasma and field measurements in NASA's Magnetospheric Multiscale (MMS) mission  4 satellites are operating in close formation  Group leads investigation, designed DPU board and S/W, integrated and tested 9 Flight Models (8 FM’s delivered to NASA, spare FM kept for reference measurements)  Challenges: Simultaneous manufacture, test and operation in Europe and the US  Torkar et al., 2014, Active S/C Potential Control Investigation, Space Science Reviews, /s IWF/ÖAW GRAZ4 ASPOC for Magnetospheric Multiscale Geometry of the ion beams ASPOC instrument

Concept  All-sky camera for ions in Mercury's exo-ionosphere  3D velocity distribution and mass spectrum for ions over a full 2π FOV, up to ~3 keV energies and in a mass range extending up to ~132 amu Key elements  Ellipsoidal electrostatic mirror M1 for focusing charged particles  Toroidal electrostatic analyzer for the energy selection by pass-band  Gate electrodes for providing start time for the time of flight (TOF)  Multi channel plate for detecting the ion impact as to both TOF and imaging IWF/ÖAW GRAZ5 PICAM: Planetary Ion Camera Schematics of the ion optics

PICAM is part of the SERENA suite of four sensors. Joint development with contributions from  France (detector, ion optics)  Germany (high voltage control, gate driver)  Hungary (DC converter)  Ireland (electronic box) IWF leads the investigation and is responsible for  digital processing unit and ion optics  flight software and EGSE  mechanical and electrical integration  functional testing and environmental testing  performance calibration IWF/ÖAW GRAZ6 PICAM for Bepi Colombo PICAM flight model DPU flight board

Mechanical and electrical integration  Demanding requirements as to mechanical fitting accuracy, harness routing, general handling and cleanliness Functional and performance testing  Operational parameters for electrodes as crucial point for the overall performance Test facilities  High variance as to beam elevation (~90°), beam azimuth (~20°), unit rotation (~360°) and input parameters (electrode voltages) as challenge for the ion gun test facility IWF/ÖAW GRAZ7 PICAM: Integration and Testing PICAM sensor cross section Current measurements

MMS ASPOC  Ground testing, operations planning until launch in March 2015  In-orbit commissioning, followed by routine operations of 8 instruments  Science data analysis (Nakamura et al.) BepiColombo PICAM  Delivery of PICAM FM by the end of 2014  Refurbishment of PICAM QM as flight spare  Support of tests on observatory level  Performance testing and verification of PICAM flight spare including performance modelling  Support of the overall planning on mission level and SERENA level Future Plans: IWF/ÖAW GRAZ8 PICAM QM on MPO

IWF/ÖAW9 Thank you