Physics

Question 1

What are the assumptions of Bragg-Gray cavity theory?

Answer 1

Essentially both that the chamber is large and small:
1. That charged particle equilibrium exists
2. All electrons causing ionization in the cavity arise in the phantom (so the cavity is small)
3. Secondary electron spectrum is unchanged by the cavity (so the cavity is small)
4. Energy is deposited locally (so the cavity is big)

Question 2

What change does spencer-attix cavity theory make from Bragg-Gray?

Answer 2

Does away with the need to assume the cavity is large by using restricted mass collisional stopping power rather than the mass collisional stopping power. Applies to small cavities

Question 3

What is the assumption of Burlin cavity theory?

Answer 3

Just that charged particle equilibrium exists.