COMPUTER SIMULATION OF GAS-FILLED SEPARATORS.
II. ION CHARGE FLUCTUATIONS
S. S. Olennikova, A. P. Shcherbakov
Institute for Analytical Instrumentation RAS, Saint-Petersburg
The paper presents a mathematical
model of ion charge fluctuations at collisions with gas molecules, which
takes into account one-electron trapping and one- or two-electron loss effects.
The model is the simplest gener-alization of the single-electron fluctuation
model and gives asymmetrical equilibrium charge distributions. It is shown
that for symmetrical charge distributions in the ion beam, ion charge fluctuations
lead to an increase in the average radius of curvature of the ion trajectory
in a magnetic field. For asymmetrical charge distributions, this radius may
either increase or decrease. The results of numerical modeling of ion motion
in gas-filled sepa-rators show that the allowance for two-electron processes
yields substantially different ion distributions in the beam in the focal
plane of the separator.