IEET-2016

Method for Calculating the Potential Distribution of Nonlinear Ion Mirror and Modeling a Dust-Impact Mass Spectrometer

Piyakov, I., Rodin, D., Rodina, M.

Abstract.Dust-impact mass spectrometers are used to analyze the chemical composition of micrometeoroids and space debris particles. The focusing of charged particles packets produced by high-speed interaction is complicated because of their high energy spread. The focusing can be achieved by using high voltages, or using electrical fields with special distributions. The method of analytical calculation of such nonlinear distribution is given in this paper. The nonlinear electrostatic ion mirror with a given distribution of potential provides the temporal focusing of ions with an energy spread of up to 25% of the accelerating voltage. To verify the focusing ability of the resulting potential distribution the trajec-tories of ions with different coordinates of origin and different initial energy spread were calculated. The mass resolution is calculated on the basis of ions trajectories and times of flight. The results of trajectories simulation allow us to conclude that nonlinear ion mirror provides sufficient level of temporal focusing to resolve simple substances such as aluminium, ferrum, lithium and other metals that can be detected in the chemical composition of micrometeoroids and space debris particles.

Keywords:dust-impact mass spectrometer, time of flight mass spectrometer, mass analyzer, nonlinear ion mirror, reflectron