Mars Oxidant and Radical Detector MORD

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Mars Oxidant and Radical Detector (MORD)
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Superoxide Radicals O2-, Si-O-O
Principle of EPR
Concentration, 1 35 ppm Detection Limit gt 50 ppb
Magnetic Field Scan _at_ Fixed Freq. Freq. Scan _at_
Fixed Magnetic Field
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Technical Accomplishments

• Design/fabrication/testing of an improved
  narrowband EPR resonator (7.58.5 GHz), for
  samples of larger diameter (up to 5 mm).
• Design/fabrication/testing of a wideband EPR
  resonator (2-8 GHz) for detection of transition
  metal ions. Refinement for higher spectral
  sensitivity is on-going.
• Design/fabrication of sample belt assembly.
• We have submitted a proposal to MSL AO, Radicals
  and Oxidants Investigation, ROXI.

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Frequency Scan EPR
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Narrowband EPRScan Range7.5-8.5 GHz, _at_ 2.8
KGauss
Wideband EPR Scan Range 2-8 GHz _at_ 1 kGauss
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Narrowband EPR
Laboratory EPR experiments show that
superoxide radicals form under a simulated
martian environment Yen et al., 2000
Frequency scan EPR developed through PIDDP and
HEDS funding demonstrate feasibility of
concept (currently TRL 4)
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Wideband EPRWideband Tunable Resonator (2-8 GHz)

• We have designed and fabricated a new wideband
  (2- 8 GHz) tunable EPR resonator for MORD
  application. Test/refinement is in progress.

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Example of Mixed Sample EPR
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Mn2 ion as EPR Calibration Standard
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Sample Belt (Design)

• After evaluation of many synthetic materials such
  as, Kevlar, Polypropylene, Vectran,
  Polybenzooxazole (PBO), Glassfiber, we have
  decided to mold the sample belt out of Silicone
  Rubber. Kirkhill-TA (Brea, CA) fabricated the
  belt under a JPL contract. Amount of each sample
  in the belt is 10 mg.
• Silicone Rubber has very little background EPR
  signal, and satisfactory temperature
  characteristics over a wide range, -60 230 C.

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Fabricated Sample Belt(Molded Silicone Rubber)
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MSL ROXI Sample Handling System
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MSL ROXI Sample Handling System