Podcast
Questions and Answers
What is the effect of low energy beam contamination on the entrance region?
What is the effect of low energy beam contamination on the entrance region?
- It increases the peak/entrance ratio
- It has no effect on the entrance region
- It may affect the entrance region (correct)
- It causes a decrease in dose at the entrance region
How does a short effective source distance affect the peak/entrance ratio?
How does a short effective source distance affect the peak/entrance ratio?
- It makes the peak wider
- It has no effect on the peak/entrance ratio
- It increases the peak/entrance ratio
- It decreases the peak/entrance ratio (correct)
What is the impact of non-elastic nuclear reactions on dose distribution?
What is the impact of non-elastic nuclear reactions on dose distribution?
- They increase dose at the entrance region
- They make the peak narrower
- They have no impact on dose distribution
- They move dose from the peak upstream (correct)
What makes active range modulation more complicated than passive range modulation?
What makes active range modulation more complicated than passive range modulation?
What happens to the Bragg peak as depth increases?
What happens to the Bragg peak as depth increases?
What is the main reason for the difference in dosimeter response between Ionisation Chamber and Faraday Cup?
What is the main reason for the difference in dosimeter response between Ionisation Chamber and Faraday Cup?
In proton therapy accelerators, what is the classification of proton energies for the intermediate energy range?
In proton therapy accelerators, what is the classification of proton energies for the intermediate energy range?
What is the dominant component of the prompt radiation field produced by protons in the therapeutic energy range of 67–330 MeV?
What is the dominant component of the prompt radiation field produced by protons in the therapeutic energy range of 67–330 MeV?
Which factor mainly determines the effective mass stopping power from experimental data?
Which factor mainly determines the effective mass stopping power from experimental data?
What is responsible for the production of secondary particles in proton therapy accelerators?
What is responsible for the production of secondary particles in proton therapy accelerators?
What is the significance of the fact that the coefficient is not very material-dependent in the context of stopping depths?
What is the significance of the fact that the coefficient is not very material-dependent in the context of stopping depths?
How do materials other than water affecting the incident proton energy impact the Bragg curve?
How do materials other than water affecting the incident proton energy impact the Bragg curve?
In the context of cyclotron-based therapy facilities, why are degraders used to change the beam energy?
In the context of cyclotron-based therapy facilities, why are degraders used to change the beam energy?
What is the main effect of multiple Coulomb scattering on protons passing through a slab of material?
What is the main effect of multiple Coulomb scattering on protons passing through a slab of material?
What is the task of multiple scattering theory in predicting θ0 for protons passing through a slab of material?
What is the task of multiple scattering theory in predicting θ0 for protons passing through a slab of material?
In the context of the text, what does the term 'transverse equilibrium' refer to?
In the context of the text, what does the term 'transverse equilibrium' refer to?
How does using a large ion chamber differ from using a small ion chamber in a sufficiently broad beam?
How does using a large ion chamber differ from using a small ion chamber in a sufficiently broad beam?
What happens to the dose on axis in a sufficiently broad beam as depth increases?
What happens to the dose on axis in a sufficiently broad beam as depth increases?
What is the purpose of applying a large number of Pencil Beams (PBs) close together and doing a depth scan with a small Ionization Chamber?
What is the purpose of applying a large number of Pencil Beams (PBs) close together and doing a depth scan with a small Ionization Chamber?
How does the effective mass stopping power compare when measured using a small Ionization Chamber and a large 'pancake' Ionization Chamber?
How does the effective mass stopping power compare when measured using a small Ionization Chamber and a large 'pancake' Ionization Chamber?