Inficon Transpector CPM User Manual

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Transpector CPM Operating Manual
5.2.2.2 The Zero Blast
When the RGA scans over the very low end of the mass spectrum, the RF and DC
voltages applied to the rods approach zero. The quadrupole then ceases to act as
a filter and a large current of unseparated ions is detected, called the zero blast.
(See Figure 5-4.)
Zero blast will interfere with the observation of masses 1 and 2 in the higher
pressure range of the RGA (i.e., 1E-6 Torr to 5E-4 Torr) when significant quantities
of higher-mass ions are present. The zero blast contribution to the mass 2 signal
intensity can be between 5 ppm and 100 ppm depending on the mass range of the
RGA.
Figure 5-4 The zero blast
Zero Blast signal contribution

Inficon Transpector CPM Specifications

General

Brand	Inficon
Model	Transpector CPM
Category	Industrial Equipment
Language	English