Agilent Technologies 7000 Triple Quadrupole GC/MS, Maintenance Manual

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Analyzers and Collision Cell
7
Troubleshooting and Maintenance Manual 147
The collision cell
The precursor ions selected by the front quadrupole collide with a reaction
gas, typically a nitrogen/helium mixture. This generates additional product
ions.
The pre-filter
This device, located on the entrance of the rear analyzer, transfers the
remaining precursor ions and the product ions generated in the collision cell
to the rear analyzer. It also aligns the rear of the collision cell with the rear
analyzer.
The rear analyzer
The rear analyzer consists of the rear quadrupole, the detector, and a
heater/sensor assembly.
The ion stream now consists of the ions selected by the front analyzer and the
ions formed by collision with the reaction gas. The rear analyzer separates
these ions and passes them to the detector.
The detector
Ions that pass the rear analyzer strike a high-energy dynode, where they
generate secondary electrons. These enter a multiplier and are collected to
become the output signal.