Charge separation in a magnetized 3D plasma-sheath-lens is demonstrated by simulations and experiments. The presence of the magnetic field makes the charge kinetics within the potential structure of the sheath mass selective. This fact combined with previously demonstrated discrete and modal focusing effects provides a possibility to detect mass peaks from 1 up to a few hundreds units atomic mass using a magnetized plasma-sheath-lenses of a few cm in diameter. Experiments are performed in a device operated at pressures below 10 mTorr with three ECR plasma cells in gas mixtures of Ar/SF_6/O_2. An axial magnetic field adjustable from 0 up to 600 Gauss is created by two coils. Mass spectra are visualized measuring the etching profile resulted by the incidence of different ions species on the electrode creating the plasma-sheath-lens.
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