1. Influence of photolysis on multispectral photoacoustic measurement of nitrogen dioxide concentration.
- Author
-
Tian, Guoxun, Moosmüller, Hans, and Arnott, W. Patrick
- Subjects
ATMOSPHERIC nitrogen dioxide ,PHOTOLYSIS (Chemistry) ,PHOTOACOUSTIC spectroscopy ,ENERGY budget (Geophysics) ,RADIATION ,SIGNAL processing - Abstract
Multispectral photoacoustic instruments are commonly used to measure aerosol and nitrogen dioxide (NO2) light absorption coefficients to determine the radiation budget of the atmosphere. Here a new photoacoustic system is developed to explore the effect of photolysis on the measured signal in a multispectral photoacoustic spectrometer. In this system, a 405-nm laser is used primarily as light source for photolysis. Additionally, a well-overlapped 532-nm laser, modulated at the resonant frequency of the photoacoustic instrument, is used to probe the NO2concentration. As a result, the photolysis effect at 405 nm can be observed by the photoacoustic instrument through the 532-nm laser. This work determines an 11% reduction of the photoacoustic signal caused by the photolysis effect for typical conditions, which needs to be taken into account when calibrating multispectral photoacoustic spectrometers with NO2. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF