A Three-Dimensional Quadrupolar Mass Analyzer. II. Operational Characteristics.

摘要

The properties of a 3DQ mass analyzer constructed are described. Ion-generation and withdrawal pulses are made coherent with the radio frequency (rf) driving voltage. This allows the rf phase dependence of these events to be measured;in addition,lifetimes of stored ions can be conveniently measured. Representative results of lifetime studies on N2(+) at various background pressures and rf frequencies are given. The maximum intensity and the area of the N2(+) peak are observed as functions of the dc-to-rf voltage ratio,rf frequency,repetition rate of the ionization withdrawal sequence,background pressure,and storage time. (Author)