46. NUCLEAR MEDICINE: PROTON EMISSION Flashcards
1
Q
- How do Proton-rich nuclides normally approach stability?
A
THEY DO THIS:
- trough Beta + Decay
- or through Alpha Decay
2
Q
- What happens when we have extreme cases elements with large proton excess?
A
- a nucleus may move towards stability
- it does this through the emission of one or two protons
3
Q
- What processes does Proton Emission (PE) compete with?
A
- Beta + Decay
- Alpha Decay
PROTON EMISSION:
- is the rarest type of decay
- it is not observed in naturally occurring radionuclides
4
Q
- What happens in Proton Emission Decay?
A
- the atomic number (Z) decreases by 1
- this means that one proton is released
- the Atomic Mass Number (A) decreases by 1
- this means that one neutron is also released
5
Q
- What happens when a proton is ejected from a Radionuclide?
A
- the Parent Nucleus (P) sheds an orbital electron
- this is shed from the outermost shell
- the daughter atom becomes neutral
6
Q
- What happens to the ejected Proton?
A
- the energetic proton slows down
- this results from moving through the absorbed
medium - the proton captures an electron from its surroundings
- this results in a neutral hydrogen atom
7
Q
- What happens to the number of Neutrons in Proton Emission decay?
A
- the number of neutrons id unchanged
- the Parent (P) nucleus and the Daughter (D) nucleus ae
now known as ISOTONES
8
Q
- For which kinds of Nuclides is Proton Emission Decay likely to take place?
A
- lighter nuclides
- proton rich nuclides
- that have an odd number of protons (Z)
9
Q
- When does a simultaneous, two-proton emission occur?
A
WHEN WE HAVE NUCLIDES THAT ARE:
- lighter
- very proton rich
- that have an atomic mass number around 50
- that have an even number of protons
10
Q
- What is one example of Proton Emission Decay?
A
- the decay of Lithium-5
- into Helium-4
- it now has a half life of 10⎺²¹ seconds
