Darmstadt 2008 – scientific programme
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UP: Fachverband Umweltphysik
UP 6: Poster: Atmosphäre und Aerosole: Instrumentelles und Laboruntersuchungen
UP 6.1: Poster
Tuesday, March 11, 2008, 16:30–19:00, Poster B1
Recent advances in the application of light-emitting diodes as light sources in active DOAS measurements — Holger Sihler, •Christoph Kern, and Ulrich Platt — Institute of Environmental Physics, Heidelberg, Germany
The Long Path Differential Optical Absorption Spectroscopy (LP-DOAS) technique is a well established method for measuring atmospheric trace gases. The application of light-emitting-diodes (LEDs) as artificial light sources represent a very advantageous alternative to common xenon-arc lamps. LEDs are smaller, lighter, cheaper, more durable and less power consuming.
Now, measurements in the deep ultra-violet wavelength range became possible due to recent developments of UV-LEDs based on III-nitride semiconductor materials. Their first application in active DOAS measurements is presented. The trace gas concentrations of SO2, O3, NO2, and CH2O were measured in the wavelength range between 297 and 309 nm.
Furthermore, a compact active DOAS instrument was built, which is entirely battery powered, and therefore well-suited for field measurements in remote areas. As an example, preliminary results of measurements in the plume of Masaya Volcano, Nicaragua, are given.