Abstract:
A detection system and a method for detecting ions which have been separated in a time-of-flight (TOF) mass analyzer, comprising an amplifying arrangement for converting ions into packets of secondary particles and amplifying the packets of secondary particles, wherein the amplifying arrangement is arranged so that each packet of secondary particles produces at least a first output and a second output separated in time and so that during the delay between producing the first and second output the first output produced by a packet of secondary particles is used for modulating the second output produced by the same packet. An increased dynamic range of detection and protection of the detection system against intense ion pulses is thereby provided.
Abstract:
A method of switching between two modes of power supply to a mass analyzer is provided. In a first mode of operation, operated for a first predefined time duration, a first power supply, coupled to the mass analyzer, generates a first nonzero potential, while a second power supply, disconnected from the mass analyzer, generates a second non-zero potential. In a second mode of operation, operated for a second predefined time duration, the second potential is coupled to the mass analyzer, while the first power supply, disconnected from the mass analyzer, generates the first potential. These predefined time durations are selected such that only one of: the first potential; and the second potential is coupled to the mass analyzer at any time, and such that the first and second modes of operation are carried out at least once within a predetermined length of time.
Abstract:
An ion transfer tube for a mass spectrometer comprises a core member and a first jacket tube member at least partially enclosing the core member and providing one or more channels therethrough. A method of forming an ion transfer tube, comprises: providing a first jacket tube member having a length and an internal bore, the internal bore passing along the length and defining an interior surface of circular cross section; removing at least one portion of the first jacket tube member adjacent to the interior surface so as to form at least one groove, channel, slot, recess or embayment of or in the interior surface; and providing a core member within the bore of the jacket tube member such that remnant portions of the interior surface of circular cross section mate against portions of an exterior surface of the core member.
Abstract:
This invention relates to mass spectrometry that includes ion trapping in at least one of the stages of mass analysis. In particular, although not exclusively, this invention relates to tandem mass spectrometry where precursor ions and fragment ions are analyzed. A method of mass spectrometry is provided comprising the sequential steps of: accumulating in an ion store a sample of one type of ions to be analyzed; accumulating in the ion store a sample of another type of ions to be analyzed; and mass analyzing the combined samples of the ions; wherein the method comprises accumulating the sample of the one type of ions and/or the sample of another type of ions to achieve a target number of ions based on the results of a previous measurement of the respective type of ions.
Abstract:
Embodiments of the invention provide a detection apparatus for detecting charged particles having a secondary particle generator for generating secondary charged particles in response to receiving incoming charged particles, a charged particle detector for receiving and detecting secondary charged particles generated by the secondary particle generator, a photon generator for generating photons in response to receiving secondary charged particles generated by the secondary particle generator, and a photon detector for detecting the photons generated by the photon generator.
Abstract:
Mass analysers and methods of ion detection for a mass analyser are provided. An electrostatic field generator provides an electrostatic field causing ion packets to oscillate along a direction. A pulse transient signal is detected over a time duration that is significantly shorter than a period of the ion oscillation or using pulse detection electrodes having a width that is significantly smaller than a span of ion harmonic motion. A harmonic transient signal is also detected. Ion intensity with respect to mass-to-charge ratio is then identified based on the pulse transient signal and the harmonic transient signal.
Abstract:
A system and method of mass spectrometry is provided. Ions from an ion source are stored in a first ion storage device and in a second ion storage device. Ions are ejected from the first ion storage device to a first mass analysis device during a first ejection time period, for analysis during a first analysis time period. Ions are ejected from the second ion storage device to a second mass analysis device during a second ejection time period. The ion storage devices are connected in series such that an ion transport aperture of the first ion storage device is in communication with an ion transport aperture of the second ion storage device. The first analysis time period and the second ejection time period at least partly overlap.
Abstract:
This invention relates to mass spectrometry that includes ion trapping in at least one of the stages of mass analysis. In particular, although not exclusively, this invention relates to tandem mass spectrometry where precursor ions and fragment ions are analysed. A method of mass spectrometry is provided comprising the sequential steps of: accumulating in an ion store a sample of one type of ions to be analysed; accumulating in the ion store a sample of another type of ions to be analysed; and mass analysing the combined samples of the ions; wherein the method comprises accumulating the sample of the one type of ions and/or the sample of another type of ions to achieve a target number of ions based on the results of a previous measurement of the respective type of ions.
Abstract:
A method of operating a gas-filled collision cell in a mass spectrometer is provided. The collision cell has a longitudinal axis. Ions are caused to enter the collision cell. A trapping field is generated within the collision cell so as to trap the ions within a trapping volume of the collision cell, the trapping volume being defined by the trapping field and extending along the longitudinal axis. Trapped ions are processed in the collision cell and a DC potential gradient is provided, using an electrode arrangement, resulting in a non-zero electric field at all points along the axial length of the trapping volume so as to cause processed ions to exit the collision cell. The electric field along the axial length of the trapping volume has a standard deviation that is no greater than its mean value.
Abstract:
The present invention provides a method of reflecting ions in a multireflection time of flight mass spectrometer comprising providing an ion mirror having a plurality of electrodes, the ion mirror having a cross section with a first, minor axis (Y) and a second, major axis (X) each perpendicular to a longitudinal axis (Z) of the ion mirror which lies generally in the direction of time of flight separation of the ions in the mirror; guiding ions towards the ion mirror; applying a voltage to the electrodes so as to create an electric field which: (a) causes the mean trajectory of the ions to intersect a plane of symmetry of the ion mirror which contains the longitudinal (Z) and major axes (X) of the mirror; (b) causes the ions to reflect in the ion mirror; and (c) causes the ions to exit the ion mirror in a direction such that the mean trajectory of ions passing through the ion mirror has a component of movement in a direction (Y) perpendicular to and diverging from the said plane of symmetry thereof.