The aim is to measure in-situ positive and negative ion composition simultaneously with a new second generation balloon-borne mass spectrometer offering higher mass and spatial resolution, an increase in absolute sensitivity and reduced fragmentation of complex ions.
This technique should result in the capability to determine in-situ the concentration of various stratospheric trace gases, either by using passive or active chemical ionization methods (eg, water, acetonitrile, nitric acid, sulphuric acid, nitrous oxide). The balloon launching site will be either Aire sur l'Adour or Gap-Tallard in France.
The activities foreseen within the present project include:
conversion of the laboratory instrument for positive ions to a balloon borne payload;
development of a similar instrument for negative ions;
development of suitable ion sources for use of the mass spectrometer in active chemical ionization applications emphasizing the method for simultaneous nitrogen pentoxide and nitric acid measurements;
laboratory measurements of rate constants of ion-molecule reactions involved with the use of the developed ion source if required;
four balloon flights for measurements in the stratosphere of respectively, positive ambient ions and related trace gases (water, acetonitrile and others), negative ambient ions and related trace gases (nitric acid and sulphuric acid), simultaneous measurements of nitric acid and nitrogen pentoxide.
Funding SchemeCSC - Cost-sharing contracts