École Polytechnique Fédérale de Lausanne

DMT Cloud Condensation Nuclei Counter (CCN-100)

PI: Prof. Nenes Athanasios (athanasios.nenes@epfl.ch); Prof. Zongbo Shi (z.shi@bham.ac.uk) Operators: Nenes Athanasios, LAPI/EPFL and CSTACC/FORTH; Ghislain Motos, LAPI/EPFL; Christos Kaltsonoudis, CSTACC/FORTH

The Droplet Measurement Technologies (DMT) Cloud Condensation Nuclei Counter (CCN) is based on the Continuous Flow Streamwise Thermal Gradient Chamber design of Roberts and Nenes, AST, (2005). The instrument CCN measures aerosol particles that can form into cloud droplets at a given level of water vapor supersaturation. The instrument operates by supersaturating sample air to the point the where the CCN become detectable particles, which are then sized using an optical particle counter and distributed into 20 bins. Supersaturation is generated by relative diffusion of warm(saturated) water vapor into colder(saturated) air, and can be controlled by the flow rate and streamwise temperature gradient maintained in the instrument. The technology is patented and licensed for manufacturing by DMT.