Ion source of DMS-01 scientific equipment for «AIST no 2» small spacecraft

The main requirements imposed upon ion sources for on-board time-of-flight mass spectrometers are considered in the paper. An approximate formula to calculate the ionization cross section of an analyte substance is given. The dependence of the probability of analyte ionization for the selected ion source design is shown. Several deigns of ion sources are proposed that provide the required width of the zone of ionization by selecting source parameters. A design of the ion source providing increased reliability and lifetime of the unit is selected for the use in scientific equipment DMS-01 installed aboard small spacecraft «AIST number 2». The results of a laboratory experiment on the operation of this design of the source are presented. The data obtained confirm the applicability of the Lotz-Drevin’s approximation formula to determine the probability of ionization of atoms or molecules of an analyte in the chosen design of the ion source.