The ion motion in a Penning trap is composed of three independent harmonic oscillations which have characteristic frequencies. Click here for a movie.
•Axial motion: Oscillation between both end caps of the trap. The frequency depends on the mass of the ion and is independent of the magnetic field strength B.
•Magnetron motion: Circular ExB drift about the trap axis. The magnetron frequency depends on the strength of both the magnetic and electric field. For a weak electric field it is practically mass independent.
•Reduced Cyclotron Motion: Circular motion perpendicular to the magnetic field axis. Its frequency is the pure cyclotron frequency reduced by the magnetron frequency.
