SuperLIBS Spectrometer

The new SuperLIBS instrument in the Mineral Spectroscopy Laboratory was designed to be analogous to the SuperCam flight instrument on the Mars 2020 mission. It was designed and built by Princeton Instruments with a NASA grant for $445,645 from the Solar System Workings program. It uses a Quantel Ultra100 laser equipped with a motorized attenuator that allows for easy adjustment of pulse energy for inter-instrument comparisons.Laser focusing optics and mounts include a filter to block visible flashlamp light, a beamsplitter to direct a portion of the beam to an energy detector, a focusing lens, and a mirror to direct the focused beam to the sample surface. Pulse energy is continuously logged with a Thorlabs pyroelectric energy sensor and meter.The ablation beam is entirely housed in an eye-safe enclosure, thereby reducing the training requirements for general users.

The SuperLIBS Mars chamber, furnished by MDC Vacuum, contains an XY translation stage with 12" range of motion, allowing for 100 5/8-in diameter samples per pump-down cycle, contained on custom sample trays. The chamber is equipped with an MKS vacuum gauge and controller and a pressure relief valve in case of accidental over-pressure. A rough pump is used to remove ambient air from the chamber, and CO2 is used to backfill the chamber to a Mars-analog atmosphere.

A custom optical assembly (demux) collects plasma emission, separates it into component wavelength regions (UV, VIS, and VIS/NIR), and directs it to three IsoPlane 160 spectrometers via fiber bundles. The IsoPlane spectrometers incorporate the same 2D CCDs that are being used on SuperCam. Princeton has also provided acquisition and calibration software.