NOTE: Unless stated otherwise, these pictures are all
© National Research Council of Canada
Do not use without permission!
NOTE:
Electrons are almost always blue (sometimes green)
Positrons are red
Photons are yellow
Sometimes "x"'s are drawn at transport vertices
Sometimes "o"'s are drawn at interaction points
Sometimes the intensity of the lines scales with the particle's energy
Some basic interaction physics:
Co-60 photon in water
Compton recoil electrons from a 1 MeV photon
20 MeV photon interacting in water
20 MeV electons in water
50 MeV photon interacting in lead
50 MeV photon interacting in lead
The effect of longitudinal magnetic fields on 20 MeV electron pencil beams:
0 Tesla, 2 Tesla, 6 Tesla, 10 Tesla, 20 Tesla.
Measurement of stopping power:
(Files to create the graphics were kindly supplied by Bruce Faddegon [NRC] and
Miller MacPherson [NRC])
Ion chambers:
Variance reduction:
Save time or reduce variance by:
Bremsstrahlung splitting Correlations: Compare this, with this Approximating photon distribitions: All bremsstrahlung included Machine-generated bremsstrahlung suppressed All bremsstrahlung suppressed
PRESTA-I vs PRESTA-II:
Electron transport near a graphite-air cavity How PRESTA-I models it What event-by-event Monte Carlo looks like How PRESTA-II models it How PRESTA-I models transport near a boundary How PRESTA-II models it
Other examples:
Electron transport in the phosphor of a TV tube Electron radiotherapy Bubble chamber simulation - all particles Bubble chamber simulation - leptons only Bubble chamber simulation - side view
Accelerator modelling:
This picture originated with Alan Nahum [RMH-Sutton] but was redrawn at SLAC for Ralph Nelson [SLAC] What it's all about
Data for the rest of these pictures was provided by Bruce Faddegon [NRC] or George Ding [NRC]: NRC mock-up of a medical accelerator Philips: 1, 2, 3, 4, 5, 6, 7, 8. Therac 20: 1, 2, 3, 4, 5. Varian 2100c: 1, 2, 3, 4. A "fly-through" a Therac 20: Approaching the monitor chamber Approaching the primary collimator Approaching the applicator Approaching the patient plane Do we hit the tumour or not?
The radiotherapy benchmark experiment:
Experimental set-up, electron trajectories Experimental set-up, photon trajectories Electron transport in the vicinity of the heterogeneity Dose perturbation behind an air heterogeneity Dose perturbation behind the aluminum heterogeneity
More contributions are welcome!
