Laser Photo-Acoustic Spectroscopy

LPAS


IMG_0194


Principle of the Measurement:
1. Excitation of ethylene inside a resonator using a modulated CO2 laser
2. Quenching of excited ethylene by collisions
3. Heat transfer leads to audible noise at the laser modulation frequency
4. Detection of noise with a microphone

Species Measured:
1. Ethylene

Time reponse:
4-20 seconds

Detection limit:
70-200 pptv

Manufacturer:
Sensor Sense

Publications:

Inter-comparison of laser photoacoustic spectroscopy and gas chromatography techniques for measurements of ethene in the atmosphere
W. C. Kuster, F. J. M. Harren, and J. A. de Gouw
Environmental Science & Technology, 39, 4581-4585 (2005).