Molecular ion source having low energy spread and single-electron-impact excitation.
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 ( less, similar twice the theoretical shot-noise limit) and has a compact and easily serviceable construction.
Spezeski
J J
JJ
Department of Physics, University of Arizona, Tucson, Arizona 85721Physics Department, Bates College, Lewiston, Maine 04240Department of Physics and Optical Sciences Center, University of Arizona, Tucson, Arizona 85721.
Ruff
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Wing
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