Molecular ion source having low energy spread and single-electron-impact excitation

1 September 1978

journal article
Published by AIP Publishing in Review of Scientific Instruments

Vol. 49 (9) , 1327-1331
https://doi.org/10.1063/1.1135578

Abstract

A cylindrically symmetric electron-bombardment ion source is described that has been useful in beam experiments with molecular ions. Measurements indicate that the ions have a kinetic-energy spread (full-width at half-maximum) of 0.5–1.0 eV, a current of several microamperes, and a population distribution that is consistent with vibrational and rotational factors resulting from single-electron-impact ionization. The source exhibits low noise (≲ twice the theoretical shot-noise limit) and has a compact and easily serviceable construction.

Keywords

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