Particle Physics

• Strange Particles differ from other particles due to : Having a strange quark, have a longer half life and decays by weak interactions.
• 4 conserved properties during interactions: Momentum, Charge, Bayron number and Lepton number.
• Momentum is conserved because the total momentum of all objects involved must be equal before and after an interaction.
• Isotopes are atoms with the same number of protons but different number of neutrons.
• The strong nuclear force holds the nucleus together.
• The strong nuclear force is repulsive between 0 fm to 0.5 fm.
• The strong nuclear force is attractive between 0.5 fm and 3 fm.
• Nuclei can be unstable due to a large number of protons or neutrons, for having a lot of energy.
• Annihilation is when a particle and its antiparticle collide and produce 2 photons. (Matter to energy)
• Pair production is when a photon produces a particle and its antiparticle. (Energy to matter)
• Annihilation


  When a particle and its antiparticle produces 2 photon.
• Pair production


  When a photon produces a particle and its antiparticle.
• Strong nuclear interaction only acts on hadrons and the exchange particle is a pion.
• The weak nuclear interaction acts on all particles and the exchange particle is a Boson.
• The electromagnetic interaction only acts on charged particles and the exchange particle is a photon.
• At what separation is the strong nuclear force repulsive?

  0 fm to 0.5 fm
• At what separation is the strong nuclear force attractive?

  0.5 fm to 3 fm
• Leptons are fundamental particles
• Bayrons have a 3 quark composition
• Mesons have a quark-antiquark composition
• Strange particle are produce in the strong nuclear interaction.
• Strange particles are decayed in the weak nuclear interaction
• Strangeness is conserved in the strong nuclear interaction but its not conserved in the weak nuclear interaction