Advanced Miniature Linear Ion Trap Mass Spectrometer (LITMS) for Space Applications

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1 Advanced Miniature Linear Ion Trap Mass Spectrometer (LIT) for Space Applications ANDREJ GRUBISIC (NASA GSFC/UMD CRESST) W. B. Brinckerhoff (PI), F. H. W. van Amerom, R. M. Danell, V. T. Pinnick, R. D. Arevalo, Jr., X. Li, D. Glavin, S. Getty, L. Hovmand, P. Chu, K. Zacny, S. Rogaki, T. Cornish, P. R. Mahaffy

2 Exploration of extreme, space environments Instrument exploring the final frontier needs to handle: - Power/Energy/Mass Limitations - Temperature extremes. - Low/High pressures - High radiation environments. - Shock and vibrations. Asteroids & comets - How did life emerge? - Did life emerge elsewhere? - Does life exist elsewhere? Planets

3 Mars Organic Molecule Analyzer (MOMA) on board ExoMars 2018 Rover MOMA- Laser For scale MOMA- is a dual-source linear ion trap capable of: Analysis of pyrolyzed and/or derivatized, gas chromatographically separated samples via electron impact (EI) ionization source. Direct sampling of crushed material at Mars ambient pressures via laser desorption ionization (LDI) Advanced analytical capabilities: SWIFT filtering of selected mass range / Pump (notional concept) ExoMars Rover

4 MOMA- Modes of Operation 1. Laser Desorption/ Ionization (LDI) source Linear Ion Trap (LIT) 2. Electron Ionization (EI) source Mars sample Ions drawn into capillary ion guide tube LDI- ion introduction Aperture valve (closes off tube after ions captured) Detectors /GC- ion introduction Effluent from the gas chromatograph 4

5 High Temperature olysis LIT = MOMA 2.0 Linear Ion Trap Mass Spectrometer LIT PLUS Dual RF Supply for extended mass range: Low Mass Limit: 20 Da High Mass Limit: 2000 Da Dual polarity (+/-) Ion Detection up to 1300 C

6 Precision Core Sampling () Subsystem Percussive drill at the end of a 5-DOF robotic arm acquires a sample core. In direct sampling mode, the core is presented to the inlet of the for LDI- analysis. Spatial resolution: < 0.4 mm (laser spot size) PreView Coring Bit

7 Precision Core Sampling () Subsystem Layer of interest is sub-sampled by a grinding wheel and collected in a high-temperature oven for pyrolysis/gc analysis and evolved gas analysis (EGA) Spatial resolution: ~ 1 mm (grinding wheel width)

8 VAPoR Oven Volatile Analysis by olysis of Regolith Dramatic improvement on the state-of-the-art design implemented in Surface-Analysis-at-Mars (SAM) instrument. Demonstrated the capability to achieve T = 1300 C (@ 60 W) under vacuum conditions, sufficient for evolution of nearly all key volatiles in geologic samples. LIT SAM

9 Detector board Pump Mass Spectrometer Subsystem Substantial enhancement over MOMA- design include: Dual RF supply (0.7 and 1.5 MHz) for expanded mass range ( Da). Pulse-counting and analog detector electronics for extended dynamic range. Switchable polarity on all key ion trap components for +/- ion detection capability. GSFC-built 266 nm pulsed YAG laser (250 mj/pulse) capable of 100 Hz bursts and rapid laser energy adjustments. Laser Brassboard Design Mars atmospheric pressure inlet system

10 LIT Extended Mass Range Implementation of Dual frequency RF power supplies enables Da mass range as demonstrated. H 3 O + 19 Da O 2 + NaI : Dm/z = 150 Da FWHM = 0.24 Da CF 3 +

11 SWIFT Filtering Stored Waveform Inverse Fourier Transform Application of a SWIFT waveform to the rods during trapping will eject all but the ions within the selected mass range(s). Mars sample 1. Laser Desorption/ Ionization (LDI) source Ions drawn into capillary ion guide tube Linear Ion Trap (LIT) 2. Electron Ionization (EI) source LDI- ion introduction Aperture valve (closes off tube after ions captured) Apply SWIFT waveform

12 Advantages of SWIFT By selective trapping of ions, SWIFT enables: Improved mass resolution in LDI- in cases of overloaded trap. Accumulation of ions of interest for improved detection sensitivity. / analysis. Montmorillonite (Clay) (Na,Ca) 0.33 (Al,Mg) 2 (Si 4 O 10 )(OH) 2 nh 2 O

13 +/- Ion Detection Capability Provides complementary information on the samples since certain compounds/elements prefer to form - over + ions. 81a + 1% Ca(ClO 4 ) 2 + Characteristic Cl 3 isotope pattern is clearly visible Ca(ClO 4 ) 3 - _ ClO 4 - Ca 2 (ClO 4 ) Mass [Da]

14 +/- Ion Detection Capability Negative ions of fragile organic molecules undergo less fragmentation, allowing identification of parent ion. + [M+H] + M = Da _ [M-H] - [M-H] -

15 Direct LDI Analysis of Core Samples Two analyte solutions spotted on the core. Rhodamine 6G inlet To [M+H] + Adenine Ion Intensity [a.u.] 443 Da M + Ion Intensity [a.u.] 135 Da Mass (Da) Sandstone Core Mass (Da) Rhodamine 6G Adenine Ion Intensity [a.u.] Analyte concentration gradients observed in the are consistent with the visual appearance of the core Core Position (mm)

16 Where to Next? 2016: LIT brassboard will be integrated into Mars ambient chamber and environmental tests at Honeybee for TRL6 demonstration : Atacama Rover Astrobiology Drilling Study (ARADS): Field test of an integrated rover drill system with Mars flight mission-ready prototype instruments : On the lookout for relevant Mission Opportunities.