PI	Nikos Mihalopoulos
Operators:	Iasonas Stavroulas, Katerina Bougiatioti
Participant	University of Crete

The Aerosol Chemical Speciation Monitor (ACSM; Aerodyne Inc.) measures aerosol mass and chemical composition (ammonium, sulfate, nitrate, chloride and organics) of non-refractory submicron aerosol particles in real-time. The ACSM is designed and built around the same technology as the Aerosol Mass Spectrometer (AMS), in which an aerodynamic particle focusing lens is combined with particle flash vaporization in high vacuum, hard electron impact ionization and final detection of the resulting ions with a commercial quadrupole mass spectrometer. During the measurement period ambient air was drawn into the ACSM through a PM1 aerosol inlet and the ACSM particle lens focuses submicron aerosol of ~40-1000 nm aerodynamic diameter. The PM1 inlet system removes particles which could cause problems for the ACSM inlet by clogging the pin hole. Measurements have a temporal resolution of 30 minutes. Mass concentrations are calculated with the recommended collection efficiency (CE) of 0.5 for all constituents.