An image charge detection assembly for a mass spectrometer comprising an image charge detector that is housed within an electrically conductive shielding enclosure, and a preamplifier, wherein at least an input stage of the preamplifier, which is electrically connected to the detector, is housed with the detector within the enclosure.

There is provided a method of operating a charge detection mass spectrometer (CDMS), the CDMS comprising an electrostatic ion trap, the electrostatic ion trap comprising a plurality of electrodes, the method comprising: a) introducing a first ion into the electrostatic ion trap at a first ion energy, b) setting the voltage of the plurality of electrodes to a first voltage map, c) obtaining first CDMS data indicative of a first ion oscillation frequency, d) obtaining an acceptable range or ranges of ion oscillation frequencies, e) changing the first ion energy to a second ion energy and/or changing the first voltage map to a second voltage map, and f) obtaining second CDMS data indicative of a second ion oscillation frequency.

Disclosed herein are various methods and apparatus for performing charge detection mass spectrometry (CDMS). In particular, techniques are disclosed for monitoring a detector signal from a CDMS device to determine how many ions are present in the ion trap (10) of the CDMS device. For example, if no ions are present the measurement can then be terminated early. Similarly, if more than one ion is present, the measurement can be terminated early, or ions can be removed from the trap (10) until only a single ion remains. Techniques are also provided for increasing the probability of there being a single ion in the trap (10). A technique for attenuating an ion beam is also provided.

An orbitrap may include elongated inner and outer electrodes, wherein the inner and outer electrodes each define two axially spaced apart electrode halves with a central transverse plane extending through the electrodes also passing between both sets of electrode halves, a cavity defined radially about and axially along the inner electrode between the two inner electrode halves and the two outer electrode halves, means for establishing an electric field configured to trap an ion in the cavity and to cause the trapped ion to rotate about, and oscillate axially along, the inner electrode, wherein the rotating and oscillating ion induces charges on the inner and outer electrode halves, and charge detection circuitry configured to detect the charges induced on the inner and on outer electrode halves, and to combine the detected charges for each oscillation to produce a measured ion charge signal.

Systems and methods are provided for performing multiplex electrostatic linear ion trap mass spectrometry. A first beam of ions is received and the first beam is split into N beams of ions using a beam splitter. N is two or more. Ions are received from only one of the N beams of ions at each entrance aperture of N entrance apertures of an electrostatic linear ion trap (ELIT). Ions from each entrance aperture of the N entrance apertures are trapped in separate linear flight paths using the ELIT, producing N separate linear flight paths. Ion oscillations in the N separate linear flight paths are measured at substantially the same time using the ELIT. The ELIT uses two concentric mirrors with N apertures to trap ions in the N separate linear flight paths. The ELIT uses an image current detector with N apertures to the measure the ion oscillations.

Methods, apparatus, and storage medium for obtaining high-resolution mass spectra and chemical maps from a sample using a subspace Fourier transform mass spectrometry (FT-MS) approach are described. The method includes conducting a first set of image data corresponding to a first group of spatial positions on the sample and a second set of image data corresponding to a second group of spatial positions on the sample; conducting a decomposition process on the first set of image data to obtain a set of basis elements; performing a reconstruction process on a second set of image data to obtain a set of reconstructed image data; performing a Fourier transform on the first and second sets of image data to obtain a first and second sets of mass spectra, respectively; and obtaining a FT-MS image for the sample based on the first set of mass spectra and the second set of mass spectra.

A method of mass spectral analysis in an analytical electrostatic trap (14) is disclosed. The electrostatic trap (14) defines an electrostatic field volume and includes trap electrodes having static and non-ramped potentials. The method comprises injecting a continuous ion beam into the electrostatic field volume.

A CDMS may include an ELIT having a charge detection cylinder (CD), a charge generator for generating a high frequency charge (HFC), a charge sensitive preamplifier (CP) having an input coupled to the CD and an output configured to produce a charge detection signal (CHD) in response to a charge induced on the CD, and a processor configured to (a) control the charge generator to induce an HFC on the CD, (b) control operation of the ELIT to cause a trapped ion to oscillate back and forth through the CD each time inducing a charge thereon, and (c) process CHD to (i) determine a gain factor as a function of the HFC induced on the CD, and (ii) modify a magnitude of the portion of CHD resulting from the charge induced on the CD by the trapped ion passing therethrough as a function of the gain factor.

Apparatus and method for processing an image-charge/current signal for an ion(s) undergoing oscillatory motion within an ion analyser apparatus. The method comprises: obtaining a recording of the image-charge/current signal (20a-20e) in the time domain. Then, by a signal processing unit, a value for the period (T) of a periodic signal component is determined within the recorded signal. Subsequently, the recorded signal is segmented into a number of successive time segments [0;T] of duration corresponding to the period (T). These lime segments are then co-registered in a first time dimension (t.sub.1) defining the period (T). The co-registered time segments are then separated along a second time dimension (t.sub.2) transverse to the first time dimension (t.sub.1). This generates a stack of time segments collectively defining a 2-dimensional (2D) function. The 2D function varies both across the stack in the first time dimension and along the stack in the second time dimension.

Disclosed herein are various methods and apparatus for performing charge detection mass spectrometry (CDMS). In particular, techniques are disclosed for monitoring a detector signal from a CDMS device to determine how many ions are present in the ion trap (10) of the CDMS device. For example, if no ions are present the measurement can then be terminated early. Similarly, if more than one ion is present, the measurement can be terminated early, or ions can be removed from the trap (10) until only a single ion remains. Techniques are also provided for increasing the probability of there being a single ion in the trap (10). A technique for attenuating an ion beam is also provided.