AOS: Ultrafine Condensation Particle Counter, 2.5 nm detection limit

The epcaoscpcuM1.b1 datastream contains measurements of aerosol concentration from the Aerosol Observing System (AOS) Ultrafine Condensation Particle Counter with a detection limit of 2.5 nm. This instrument measures sub-micron aerosol particle number concentration by condensing fluid onto particles and causing them to grow to sizes that are easily detectable by optical scattering, using a liquid such as butanol or water. The data were collected at Facility M1 (La Jolla, CA, the main site for EPCAPE on Scripps Pier), which is at the EPC site (La Jolla, CA), between February 15, 2023, and February 14, 2024. More information about the instrument can be found at the following link: Instrument Handbook.