Patent ID: 9576779
Date: 2017-02-21
CPC Classifications: H01J

Claim:
1. A method of operating a tandem mass spectrometer system comprising: accumulating ions in a high resolution RF ion trap; mass selective axial ejecting a plurality of ions out of the ion trap into a timed-ion selector, with high resolution; applying a pulsed DC voltage to the timed-ion selector, the pulsed DC voltage being modulated to match an ejection time from the ion trap for selecting a first portion of ions from the plurality of ions, corresponding to a specific m/z window; transmitting the first portion of selected ions out of the timed-ion selector into a reaction cell to dissociate at least some of the ions of the first portion of selected ions into dissociation product ions; transmitting dissociation product ions and the remaining ions of the first portion of selected ions out of the reaction cell into a mass analyzer; and mass-selectively transmitting at least some of the fragment ions and the remaining ions of the first portion of selected ions out of the mass analyzer into a detector.