Configuration and Accessories
Five-channel Multicollector
Conventional mass spectrometers utilise a single detector (Faraday cup or electron multiplier) to monitor ions separated by the mass analyser. Though simple and robust, this method is limited to one mass at once. A multicollector provides additional detectors which can be used to monitor two or more species simultaneously. This allows the mass spectrometer user to rapidly acquire data for up to five masses, with an instantaneous resolution of one part in 207, or optionally one part in 240.
The state-of-the-art SHRIMP II Multicollector offers up to five detectors simultaneously, with a mix of Faraday cup and electron multipliers, giving an instantaneous dynamic range in excess of 65000. The slit width can be independently set on each detector, under computer control, without breaking vacuum. The separation between heads can be varied without breaking vacuum, as can the focus and lateral position of the multi-collector.
The Faraday cups are monitored with advanced, low noise electrometers, operating under vacuum, and with computer-selectable feedback resistors to optimise sensitivity and speed.