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 response:
4-20 seconds

Detection limit:
70-200 pptv

Manufacturer:
Sensor Sense


Publications:

Airborne measurements of ethene from industrial sources using laser photo-acoustic spectroscopy
J.A. de Gouw, S. te Lintel Hekkert, J. Mellqvist, C. Warneke, E.L. Atlas, F.C. Fehsenfeld, A. Fried, G.J. Frost, F.J.M. Harren, J.S. Holloway, B. Lefer, R. Lueb, J.F. Meagher, D.D. Parrish, M. Patel, L. Pope, D. Richter, C. Rivera, T.B. Ryerson, J. Samuelsson, J. Walega, R.A. Washenfelder, P. Weibring and X. Zhu
Environmental Science & Technology, 43, 2437-2442 (2009).

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).