Objectif
During the course of the previous "SIDAMS" project (contract number STEP-0009-C) within the CEC-STEP programme, the design, construction and testing of a new generation of balloon borne ion mass spectrometers based upon the combination of a double focussing "Mattauch-Herzog" magnetic mass analyser and a detector allowing the simultaneous detection of a mass spectrum on the focussing plane, has been realized.
It is the intention to use this instrument in further phases of the research for in situ active chemical ionization mass spectrometry in the stratosphere. To do so suitable high pressure ion sources are and will be developed, which can be put in front of the new ion mass spectrometer and which allow the extension of the range of detectable gases to other species than those active in the natural ion chemistry.
Within the present project ion sources will be studied which should allow the simultaneous detection of HNO3 and N2O5 in the stratosphere, two gases playing an important role in the ozone depletion processes.
To adapt the active chemical ionization method for the measurement of HNO3 and N2O5 special ion sources are under development, which must lead to the production of alternatively Cl- and I- ions. As explained further on, the ion-molecule reactions of these slected ions with HNO3 and N2O5 result in NO-3 production, so that the knowledge of their respective rate constants should allow the simultaneous determination of the volume mixing ratios of nitric acid and dinitrogen pentoxide.
The present project is aimed at further developing of this work, balloon flights with the combined instrument (negative ion mass spectrometer and ion source) and the analysis of the data obtained with it. At the same time further necessary developments and refinements of the instrument will be introduced.
Champ scientifique
Appel à propositions
Data not availableRégime de financement
CSC - Cost-sharing contractsCoordinateur
1180 BRUXELLES
Belgique