Feynamn Diagrams Flashcards
1
Q
Internal Lines
A
Propagators representing transfer of momentum, energy and quantum number
2
Q
Photon γ Rules
A
- Absorbed/Emitted by leptons and quarks. Not neutrinos
- Do not change flavour
3
Q
Gluon g Rules
A
Absorbed/Emitted by quarks and gluons
4
Q
Neutral Boson Z Rules
A
- Absorbed/Emitted by leptons, quarks and neutrinos
- Does not change flavour
- Does not cross generations
5
Q
Charged Boson W Rules (Leptons)
A
- Lepton → W + Neutrino
- Does not cross generation
6
Q
Charged Boson W Rules (Quarks)
A
- Quark → quark + W
- Turns quark into a quark flavour below it
- Can cross generations
- Only flavour changing boson
7
Q
Weak Interaction Force is present when
A
- Neutrino/Antineutrino pair produced/destroyed (Z)
- Quark/Lepton flavour change (W)
8
Q
Electromagnetic Force is present when
A
Photon is involved
9
Q
If a quark-antiquark pair of the same flavour appears/disappears
A
g/γ/Z ↔ qq
Bold means anti
10
Q
If a neutrino-antineutrino pair appears/disappears
A
Z ↔ νν
11
Q
If a charged lepton-antilepton pair of the same flavour appears/disappears
A
γ/Z ↔ ll
12
Q
If a quark-antiquark of different flavours appears/disappears
A
W ↔ qq
13
Q
If a quark changes flavour
A
W is absorbed/emitted
14
Q
If nothing obvious happens
A
Internal absorption/emission of g/γ
