level: Level 1 of Particle Physics
Questions and Answers List
level questions: Level 1 of Particle Physics
| Question | Answer |
|---|---|
| Strength of forces (strong to weak) | Strong - EM - Weak - Gravity |
| How does coupling constant effect strength of a force | Higher coupling constant = stronger force |
| Color in hadrons | Attractive force only exists when it is colourless, so for mesons you have a quark and an antiquark, and then for baryons you have one of each colour (mixing 3 colours gets white) |
| What must be conserved at each vertex of a Feynmann diagram | charge, baryon number and lepton number |
| Forbidden interactions | - Something decaying into a quark and lepton (stuff will not be conserved) - Photon decaying into photons, as there is no charge for a photon - Gluons can't decay into a gluon and another force mediator, because colour rules violate it |
| Quark Decays | t -> b -> c -> s -> u <-> d |
| Wavefunction properties to remember | For fermions, total wavefunction is antisymmetric For ground state spacial wfn is symmetric Colour wavefunction is antisymmetric |