A Simple Ion Source for Monoenergetic Multiply Charged Ion Beams

A small and inexpensive electron beam ion source for multiply charged ions of noble gases is described. One of its essential characteristics is the low energy spread of the extracted ion beam, which depends on the charge state q of the ions and amounts to ∽q × 50 meV. The total ion current containing ionic states up to q = 6 is in the order of 10 nA. The design, construction and important parameters of the ion source are described.