ion cyclotron resonance mass spectrometer (ICRMS)

An ion cyclotron resonance mass spectrometer (ICRMS) is a device for storage and mass analysis of ions. The ions are held in the cell by a combination of a static magnetic field and a coincident electrical field generated by potentials applied to all walls of the metal cell. Ions attain a coherent cyclotron orbit  with frequency proportional to mass. Ions are detected by monitoring the alternating electrical current generated in  detector plates by their regular orbits. A Fourier transformation converts the monitored frequency to ion mass.