PEACh – Planetary Environment & Analysis Chamber

Chamber and feedthroughs

  • Chamber: 24” x 24” x 24” stainless steel
  • View port #1: 6” x 4” rectangular
  • View port #2:  circular 4.5” diameter
  • Electric Feedthroughs: three on left wall
  • Optical fiber feedthroughs: four on the ceiling
  • Feedthroughs for valves and pressure meter: three on right wall
  • Feedthroughs for coolant: two on right wall

Vacuum system

  •  Scroll pump (Edwards XDS35i): Ultimate vacuum (total pressure): 0.008 Torr
  • Pressure meter:  convection-enhanced Pirani gauge (Kurt J. Lesker Company® model KJL300808)    Vacuum reached:  ~1×10-2 mbar when maintaining the continuous pumping

Input system for gas mixture

  • Ball and Needle valves
  • CO2 (or desired gaseous mixture) in the pressure range 1×10-2 mbar to ambient pressure

Sample temperature

  • Coolant: LN2
  • Delivery of coolant: evaporation of LN2 from a Dewar via the heating of an immersed electric resistor
  • T control: RTD and CN7600 autotune controller (OMEGA Engineering Inc.)
  • Cold plate: a toroid-shape double-wall copper block
  • Sample cups: 24 cups of 0.5” internal diameter × 0.4” internal depth made of cooper in good thermal contact with cold plate
  • T range: RT to -100°C
  • Sample T homogeneity:  ±0.5 °C at 0°C or ±5 °C at – 40 °C

Chamber T & RH monitoring

  • T & RH data logger (Extech Instruments RHT20)

Imager and Spectral Sensors

Raman equipment
  • Laser: 532nm CW laser beam, ~ 10 mW at sample
  • Raman Probe: 5 mm WD, ~ 20 µm Ø laser beam, 200 μm core Ø collecting optical fiber
  • Raman spectrograph: 100 – 4300 cm-1, 4-5 cm-1 spectral resolution
LIBS equipment
  • Laser: 1064 nm with 7ns pulse width, 1-15 Hz, free-space laser delivery through view port #2
  • Collecting optical fiber: 230 µm Ø UV enhanced optical fiber cable (Ocean Optics)
  • LIBS spectrograph:  Echelle grating spectrograph with ICCD as detector (Andor Company)
  • GigE™ video camera with1.05um/pixel and 1200 μm × 1100 μm field of view
  • Co-axis with LIBS laser optical path
Sample preparations
  • Solid sample – to be placed in sample cups.
  • Liquid sample – to be placed in sample cups.