International Journal of Mass Spectrometry and Ion Physics
Simultaneous detection of a mass spectrum using a channeltron electron multiplier array
Abstract
A simultaneous ion detector is described, consisting of a channeltron electron multiplier array with phosphor screen and a vidicon—multichannel analyser combination. Conversion factors and resolutions of the different components were measured. The detector system allows 100 equidistant ion line images to be resolved at 10% valley definition. Ion currents of minimally 3 · 10−16 A could be monitored directly at the cathode ray tube (CRT) screen; the minimum number of ions necessary to produce a detectable peak is approximately 220. Spectra of krypton and xenon, obtained with a single focussing magnetic instrument, show a maximum ratio of simultaneously detectable masses of 1.16 and a 2% peak amplitude accuracy. Potentially, the new detector could fine wide application in the analysis of minute sample quantities, in the recording of extremely short lasting ion events and in the alignment or focussing improvement of ion optical apparatus.
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Detectors
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