Abstract: Provided herein are methods and systems for controlling the number of ions in a batch of ions accumulated in an ion trap. The ion trap comprises one or more detection electrodes configured to detect image current signals from ions accumulated within the ion trap. An ion or group of ions passed to the ion trap is caused to impact upon one or more of the detection electrode(s) of the ion trap so as to provide a detected signal. An ion current or charge of the ion or group of ions is determined from the detected signal, and the determined ion current or charge of the ion or group of ions is used to control the number of ions in a batch of ions subsequently accumulated in the ion trap.

Abstract: Embodiments provide methods of disambiguating the spectra produced by cyclic ion analysers. Systems, methods, and computer readable media described herein can compare two sets of ion data that have been obtained using different analyser settings such that the number of passes N through the cyclic segment of the ion path taken by ions contributing to an ion peak can be determined. As a result of the determination of the number of passes N taken by ions, the physicochemical property of those ions can be unambiguously assigned to the ion peak.

Abstract: Systems, methods, and computer-readable media described provide multi-reflection time-of-flight analyser (e.g. of a type in which the ion beam is allowed to spread out relatively broadly) and methods for use in a zoom mode, in which time-of-flight perturbations induced by reflections at the deflector are cancelled out or removed, such that they do not give rise to a significant increase in the arrival time spread of ions at the detector. This accordingly facilitates high resolution operation of the analyser in the zoom mode. Furthermore, this is done in a way which allows the analyser to remain drift focussed, which in turn means that the analyser can be straightforwardly and seamlessly switched between its normal mode of operation and the zoom mode of operation.