Particle Sorting

• Hadrons are made of quarks (A level only requires up, down and strange)

^Meson                 ^Baryon

Protons and Neutrons are baryons made of (3 quarks):

• Protons: up, up, down
• Neutrons: up, down, down

• Leptons are fundamental particles.
• They consist of electrons, neutrinos and muons.
• Electrons and muons are charged, neutrinos are neutral.
• Muons are unstable and quickly decay.

The Gravitational Interaction

• Gravity attracts all matter but is too weak to have significant effects at a subatomic scale

The Electromagnetic Interaction

• Plays an important role in the forces between charged particles and is responsible for the phenomenon of electromagnetism

The Strong Interaction

• It is this force that binds atomic nuclei together and stops them from flying apart due to the mutual repulsion of their protons and is the dominant interaction in reactions and decays of most od the fundamental particles. However, leptons don't experience the strong force

The Weak Interaction

• A force that is involved in nuclear beta decay and other radioactive processes. All particles experience the weak interaction.

• A quark has a baryon number of 1/3
• An antiquark has a baryon number of -1/3

• Mesons have a baryon number of 0
• Baryons have a baryon number of 1
• Antibaryons have a baryon number of -1

• In ANY prodiuction, annihilation or decay; baryon number is always conserved (including strange particles)

• Matter -> Quarks or Leptons
• Leptons -> Atoms
• Quarks -> Hadrons
• Hadrons -> Mesons or Baryons
• Baryons -> Nuclei
• Nuclei -> Atoms