CI-ITMS
Chemical Ionization – Ion Trap Mass Spectrometer

The Chemical Ionization - Ion Trap Mass Spectrometer (CI-ITMS) is an airborne in situ spectrometer developed by the German Aerospace Center (DLR). It uses ion trap mass spectrometry to measure peroxyacetyl nitrate (PAN), peroxypropionyl nitrate (PPN), nitric acid (HNO3), and sulfur dioxide (SO2) in the troposphere and lower stratosphere. It has a time resolution of 2 seconds, a detection limit of 25 picomoles per mole, and an accuracy of better than 10% for PAN measurements. It is typically flown on the DLR Falcon research aircraft.