The particle measurement system includes several optical particle spectrometers (FSSP-300, FSSP-100, PCASP-100X, MASP) to measure size distributions of the aerosol in-situ and after drying the particles. The covered size range is 0.1µm < D < 100 µm. The total number and size distribution of ultrafine particles (D < 0.02 µm) is measured with a set of condensation nucleus counters (Condensation Particle Size Analyser) which are operated at different lower cut-off diameters. The chemical nature of the aerosol is characterised by the thermal stability of the aerosol at distinct temperatures to discriminate between sulphuric-acid like, ammonium-sulphate-like and mineral/soot aerosol particles. Additional filter samples are used to measure the absorption coefficient of the aerosol and to determine major chemical constituents by post-flight single particle analysis.
The instruments are used in various projects on board of research aircraft (Falcon, DO228, GEOPHYSICA) at test facilities (e.g. aircraft engine test stands) and ground-stations (e.g. High alpine research station Schneefernerhaus).