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Kingdon Trap. Hande Akbas Kealan Naughton Alexander Fuchs-Fuchs . Kingdon Trap. Kingdon Trap with SIMION. Create a working Kingdon trap in SIMION Results - Energy range of potentially trapped particles Improvements. What is a Kingdon Trap?. One of the first ion traps
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Kingdon Trap Hande Akbas Kealan Naughton Alexander Fuchs-Fuchs
Kingdon Trap with SIMION • Create a working Kingdon trap in SIMION • Results - Energy range of potentially trapped particles • Improvements
What is a Kingdon Trap? • One of the first ion traps • Radial trapping - two concentric cylinders with potential difference • Axial trapping -ends with higher potential • Ions are trapped in stable orbits if they possess the right angular momentum • Static applied voltage results in a radial logarithmic potential between the electrodes • Ions pulled in elliptical orbits
How it works • Static applied voltage results in a radial logarithmic potential between the electrodes • Ions pulled in elliptical orbits
The Kingdon Trap • Symmetrical device • Inner cylinder a wire • Outer cylinder a hollow tube • Put caps on the ends
Theory • Maximum and minimum energies defined by maximum and minimum orbits • Energy Max: 768 eV • Energy Minimum: 43 eV
The Trap • Outer cylinder radius: 50 mm • Length: 300 mm • Inner cylinder: 5mm • The end caps separated by a few mm
SIMION steps • Build the Geometry • Fly the first particles
Getting the particles inside • Problem: Sealed cylinder • Make injection point • This addition must be kept same potential as caps and outer cylinder, for uniform distribution
In action Getting the particles inside
Defining the energy range • Energy • Too High: Collide with outer cylinder • Too Low: Collide with inner rod
What we found • Inner rod Potential: -3200 V • Caps and cylinder: 20 V • Minimum energy: 43 eV (38 eV) • Max energy: 580 eV (768 eV) • Mass independent
Improvements • Never been reported to produce mass spectra • Modified version - Orbitrap - used as a mass spectrometer
Orbitrap • Type of mass spectrometer • outerbarrel-like electrode and coaxial inner spindle like electrode • Electric field: quadro-logarithmic potential distribution
Orbitrap • Oscillation frequency: independent of ion velocity, Inversely proportional to square root. Characteristic of the mass of the particle • High accuracy: 1-2 ppm • High resolving power: 200,000 • resolving power proportional to the number of harmonic oscillations
Conclusions • Simulation of a working ion trap • Defined energy range agrees with theory • Upgrades can be made into a working mass spectrometer