Operational Status:
- requestable, ready for deployment
General Description:
- There are two separate components to this instrument, both using quantum-cascade tunable infrared laser differential absorption spectroscopy. One module measures CO2 with an accuracy of 0.1 ppm and a time response of one second. The second measures CO, CH4, and N2O, also with the response time of one second. The two instruments share a single aircraft rack. The instrument uses an infrared tunable quantum cascade laser. Detection is via a compact long-path cell. Two lasers are configured to measure CO, CH4, and N2O, at 1 Hz frequency and with very high precision (better than 0.5, 1.0, and 0.1 ppb Hz−1/2, respectively). A second short-path cell of a new design provides high-precision CO2 measurements (better than 0.1 ppm Hz −1/2 ) using a third QC-laser.
- (top left) Long-path, dual laser, CO_CH4_N2O sensor. Flight hardware with the long-path cell, dual laser assemblies, dual detectors (in one housing), etc., on the shock-mounted optical bench. (top right) Assembly showing the purged pressure housing.
- (bottom) CO2 HAIS sensor. Flight hardware of the optical module showing (1) dual detector, (2) dual 4 cm cells, (3) QCL laser assembly.
- The QCLS in a GV rack as installed for flight.
Measurement Characteristics:
- Overall estimate of uncertainty: CO2: 0.1 ppm
- Response time: 1 s
- Precision: better than 0.1 ppm, 0.5, 1.0, and 0.1 ppb Hz−1/2 for, respectively, CO2, CO, CH4, N2O
- Other measurement characteristics (comments on signal/noise, bias limits, etc):
