Topic 1 - Particles - Additional specification info.

Question 1

PARTICLES - 3.2.1.3 - Particles, antiparticles, and photons - extra information.

Question 2

What are hospital PET scanners an application of?

Answer 2

Particle Annihilation.

Question 3

What does the PET acronym stand for?

Answer 3

Positron emitting tomography.

Question 4

Explain how a PET scanner works for a brain scan.

Answer 4

1. Positron emitting isotope given to patient.
2. This travels via bloodstream to brain.
3. Positron emitted, meets electron = annihilation.
4. Two gamma photons are produced & sensed by detectors linked to computers.
5. Image is built up inside brain for brain scan.

Question 5

Which group of patients with a medical issue, would the PET scanner be useful for?

Answer 5

Patients with a stroke.

Question 6

What is Tomography?

Answer 6

An electronic & mechanical system that performs the scan.

Question 7

In the image scanning process, why might the sensors, that are linked to computers, be located opposite from each other?

Answer 7

• They are to be recieved by 2 gamma photons.
• 2 gamma photons travel in opposite directions (to conserve momentum).