1. Primary beam attenuation factor Fp
Primary beam attentuation factor 'Fp' has been calculated for one case:
- 33keV Sodium beam;
- The beam injects at -5 radial and -2 toroidal degrees referenced to the present beamline coordinate. Which
means the beam injects towards the exit port.
- Only electron impact ionization process for Na+ to Na++ was counted;
- Ionization cross-section calculation was from prof. Crowley's Matlab code;
- Standard plasma discharge where Ip=300kA;
- Plasma temperature and density datas from Biewer and Lanier's plots with necessary interpolations.
Na+ to Na++ raw data.
Na+ to Na++ sigmav plot
Na+ to Na++ effective cross-section for a 33keV ion
Primary beam attenuation factor Fp along the trajectory.
Te and Ne profiles for 200kA standard and PPCD discharges.
Te and Ne profiles for 400kA standard and PPCD discharges.
2. One trajectory example
- The beam injects at -5 radial and -2 toroidal degrees referenced to the present beamline coordinate.
- This trajectory is the same as above
- The secondary ion beam's path length ~ 0.6m
click here
3. Sample volume shape and sizes
- The beam size is ~ 0.5cm O.D.
- Calculations have been done for the center and bottom entrance slits at current position
- No secondary sweep is included
- Entrance slits' width have been set to 2mm, 4mm, 6mm, respectively
Center slit: 2mm openning
Center slit: 4mm openning
Center slit: 6mm openning
Bottom slit: 2mm openning
Bottom slit: 4mm openning
Bottom slit: 6mm openning
Notice: The small sample volume size (~ 0.1cm thickness) may be caused by the distant entrance slits.
4. MST HIBP grounding diagram