The standard model of particle physics is used to explain and order subatomic particles.
- Particles which join together to make up all the matter we see
- There are two main groups: quarks and leptons
A quark is an elementary particle with both electric and colour charge, and mass (antiquarks are the same, except opposite types)
- Combine with other quarks to form hadrons
- Can be green, blue or red (must combine to form white to be able to exist)
- Anti-quarks can be cyan, magenta or yellow
Hadrons are particles made from quarks Baryons: made up of 3 quarks proton, neutron, lambda Mesons: made up of a quark and an antiquark pion, kaon, rho
- Elementary particle – 6 of them
- They do not undergo strong force reactions
- Electron, muon, tau and neutrinos
- Each has its antilepton
Charged leptons form particles with other leptons. Neutrinos have no charge, and very little mass, and are therefore difficult to detect, as it does not react with many things.
Are another group of elementary particles that mediate the fundamental forces of nature. Every force that happens occurs because bosons are moving between fermions.
- Photons – carry the electromagnetic force (light waves etc.)
- Gluons – carry the strong nuclear force: glues quarks together, as well as the nucleus as a whole
- W+, W- and Z bosons – carry the weak nuclear force. Can change the flavour of a fermion, causes beta decay.
- Gravitons – supposed to carry gravitational force, not explained by the Standard model.
- Higgs boson – the particle that gives mass to other particles. Believed to have been found in 2012.