Space charge effects

The resolution of FT-ICR MS system is reduced by frequency shifts due to space-charge effects.

Space charge is treated as a continuum of charge distributed over  a space region. When charge has been emitted from some region of solid surface, a cloud of charge carriers can form space charge if they are sufficiently spread out. Because of Coulomb repulsion between ions, the cyclotron frequency changes and does not reflect accurate mass spectra. Frequency shift can be minimized by using small ions population, low ions densities, a short, high amplitute of excitation waveform.

In order to get highest mass measurement accuracy, internal or external calibration strategies are used to reduce the space charge effects. Our project is to compensate these effects using support vector regression (SVR).