Kingdon trap

The orbitrap (Fig. 2.18) was invented by Makarov in 1999 [244, 245]. It can be seen as a modified Knight/Kingdon trap because of its general construction. It can also be seen as a modified quadmpole trap that uses electrostatic fields instead of dynamic. Ions move in stable trajectories both around the central electrode and in harmonic... 

Bliimel, R. (1995b). D3uiamic Kingdon trap, Phys. Rev. A51, R30-R33. 

The Kingdon trap, an ion trapping device that consists of an outer barrel-like electrode and a coaxial inner spindle-like electrode that form an electrostatic field with quadro-logarithmic potential distribution. The frequency of harmonic oscillations of the orbitally trapped ions along the axis of the electrostatic field is independent of the ion velocity and is inversely proportional to the square root of m/z so that the trap can be operated as a mass analyser using image current detection and Fourier transformation of the time domain signal. 

The trademarked term Orbitrap has been used to describe a Kingdon trap used as a mass spectrometer. 

Storage has mainly been achieved in four types of traps (11 the radio frequency or Paul trap (2) the Penning trap (3) the Kingdon electrostatic trap and (4) the magnetostatic (magnetic bottle) trap. The principles, advanlages, and disadvantages of these traps are detailed by DJ. Wineland (Science, 226, 395-400, Oct. 26, 1984). 

D.A. Church Collision measurements and excited-level lifetime measurements on ions stored in Paul, Penning and Kingdon ion traps. Phys. Rep. 228, 253 (1993)... 

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