1 Update and functional test results for SWIM David McCann Solar system physics and space technology IRF, Kiruna Supervisor: Professor Stas Barabash David McCann, IRF Workshop, Estec Title

2 START plate Analyzer high voltage plate e-e- e-e- 1. Incoming ion directed into the aperture by the electrostatic deflector. 2. Ion traversing the analyzer channel. 3. Ion hitting the conversion surface yielding electrons detected by the START CCEM. 4. Scattered neutral hitting the STOP plate yielding electrons detected by the STOP CCEM. Deflector high voltage plates START CCEM STOP CCEM STOP plate n i+i+ i+i+ TDC TOF Update and functional test results for SWIM  SWIM – Solar WInd Monitor  Low resource ion mass analyzer  Relying on time-of-flight technique  From significant point of view, a little sister to the MIPA sensor included in the SERENA package accepted to fly on-board the ESA BepiColombo MPO mission to Mercury (2014?)  Launch Mar 2008 on the Indian Chandrayaan-1 mission to the Moon David McCann, IRF Workshop, Estec Introduction

3 Two major modules: i) sensor head ii) electronics board housing David McCann, IRF Workshop, Estec Sensor characteristics Energy range~10 eV – 15 keV Energy resolution,  E/E 7% Viewing angle Angular resolution 9 o x 180 o 9° x 22.5° Mass resolutionH, He, O, Na/Al-group, K/Ca-group, Mn/Fe Energy–elevation cycle8 sec Geometric factor, total0.14 cm 2 sr eV Update and functional test results for SWIM

4 Primary objective:  Monitoring of the solar wind to support sputtered/back scattered ENA studies Secondary objectives:  Investigating the possible occurrence of local magnetic fields on the lunar surface.  Studying sputtered ions from the lunar surface to investigate eg. permanently shadowed areas.  Studying the dynamic structure of the lunar wake. David McCann, IRF Workshop, Estec Scientific objectives Update and functional test results for SWIM

5  Tests performed at the calibration facilities at IRF, Kiruna.  Capable of creating ions with energies up to 50keV/q  Various species (H +, H 2 +, H 3 +, O +, H 2 O +, N 2 + /O 2 +, Ar + )  Pressure ~ 3-4*10 -7 mbar David McCann, IRF Workshop, Estec Test setup Update and functional test results for SWIM

6 David McCann, IRF Workshop, Estec Test setup Update and functional test results for SWIM

7  Several issues regarding the HVPS was identified  Ripple on the high voltage outputs  Non-zero minimum on high voltages  Mechanical manufacturing error  Analyzer channel walls not aligned to the same origo David McCann, IRF Workshop, Estec Functional test outcome mm mm Analyzer high voltage plate e-e- Deflector high voltage plates START plate START CCEM STOP CCEM STOP plate i+i+ i+i+ TOF Update and functional test results for SWIM

8  Different settings to the deflector plates will scan through the azimuthal acceptance angle.  Plot showing pixel size at certain viewing angels.  Bold boxes is from calibrations, hollow markers from simulations.  Pixel size increasing with increasing angle. David McCann, IRF Workshop, Estec Functional test outcome Update and functional test results for SWIM

9  TOF spectra for H + and H 2 O +.  Nicely separated primary particle peaks  Ion recoil problem  Seems to be unavoidable?  Can be subtracted from results by calibration of occurrence. David McCann, IRF Workshop, Estec Functional test outcome Update and functional test results for SWIM

10  TOF spectra for H 2 O + using different post-acceleration settings.  One can clearly see the influence on the TOF-spectra. David McCann, IRF Workshop, Estec Functional test outcome Update and functional test results for SWIM

11  Several issues regarding hardware were identified and corrected for.  The instrument performance meets the specifications in most aspects.  FM calibrations will thoroughly determine performance and prefered sensor settings.  Major point still pending satisfactory solution is the ion recoil problem.  FM calibrations will start during October 2006  Good luck in trying to get hold of David during the fall/winter of David McCann, IRF Workshop, Estec Functional test summary Update and functional test results for SWIM

12 Update and functional test results for SWIM David McCann Solar system physics and space technology IRF, Kiruna Supervisor: Professor Stas Barabash David McCann, IRF Workshop, Estec Title