41. NUCLEAR MEDICINE: BETA DECAY

Question 1

1. What happens during Beta (β) Decay?

Answer 1

• the atomic number (Z) of the parent nuclide changes
  by one unit
• it can either increase by 1
• or decrease by 1
• the mass number (A) of the parent nuclide remains
  constant

Question 2

2. What is conserved during the Beta Decay process?

Answer 2

• the number of nucleons
• the total charge

Question 3

3. What is the daughter nucleus (D) refereed to as?

Answer 3

• an Isobar of the parent (P)
• this means that they are nuclides of different chemical
  elements
• they have the same Atomic Mass
• they have different Atomic Numbers

Question 4

4. What are the 3 processes of Beta Decay?

Answer 4

1. Beta Minus (β-) Decay
2. Beta Plus (β+) Decay
3. Electron Capture

Question 5

5. What is Beta Minus (β-) Decay?

Answer 5

• this is when there is an excess number of neutrons
• these are converted into protons
• this is done through the emission of an electron and an
  anti-neutrino

Question 6

6. What are the products of Beta Minus Decay?

Answer 6

1. A DAUGHTER NUCLEUS:
   
   • it has one more proton than the parent
   • it has one less neutrons than the parent
2. AN ANTINEUTRINO
3. AN ELECTRON

Question 7

7. What is Beta Plus (β+) Decay?

Answer 7

• this is when there is an excess number of protons
• these are converted into neutrons
• this is done through the emission of a neutrino and a
  positron

Question 8

8. What are the products of Beta Plus Decay?

Answer 8

1. A DAUGHTER NUCLEUS:
   - it has one less proton than the parent
   - it has one more neutron than the parent
2. A NEUTRINO
3. A POSITRON

Question 9

9. What is Electron Capture?

Answer 9

• this is when an electron is added to the parent nucleus

Question 10

10. What are the products of Electron Capture?

Answer 10

1. A DAUGHTER NUCLEUS:
   - it has one less proton than the parent
   - it has one more neutron than the parent
2. A NEUTRINO

Question 11

11. In many Beta Decay cases, what does the decay of the parent nucleus lead to?

Answer 11

• it leads to an unstable state of the daughter
• it leads to a metastable excited state of the daughter
• it does not lead directly to the ground state of the
  daughter nucleus

Question 12

12. How does the excited state of the daughter nucleus de-excite?

Answer 12

• it does this through the emission of the gamma rays
• it can also do this through the emission of internal
  conversion electrons

Question 13

13. When can Beta Decay only take place?

Answer 13

• when the binding energy of the daughter nucleus
  EXCEEDS the Binding energy of the Parent Nucleus

Question 14

14. What is the Binding energy?

Answer 14

• this is the smallest amount of energy needed to
  remove a particle from a system