Particles + Radiation

• Specific charge


  The charge per unit mass of a particle
• Isotope


  Atoms of the same element that have different numbers of neutrons
• Forces within the nucleus

  Electrostatic repulsion between protons, strong nuclear force between nucleons
• Strong nuclear force within the nucleus

  Repulsive between 0-0.5fm, Attractive between 0.5-3fm, negligible beyond 5fm
• What is an unstable nucleus?

  Nuclei which have too many protons, neutrons or both such that the SNF cannot hold them together
• What are the types of decay?

  Alpha, Beta, Gamma
• Alpha Decay Equation


  Mass decreases by 4, atomic number decreases by 2, alpha particle emitted
• Beta Minus Decay Equation

  A type of decay in which an unstable nucleus of an atom emits a beta-minus particle (an electron) and an electron antineutrino.
• Beta Plus Decay Equation

  A type of decay in which an unstable nucleus of an atom emits a beta-plus particle (positron) and an electron neutrino
• Similarities between particles and antiparticles

  Mass, rest energy
• Differences between particles and antiparticles

  Charge, quark structures (Hadrons only)
• Annihilation


  a particle and its corresponding antiparticle collide, as a result their masses are converted into energy
• Pair Production


  a photon is converted into an equal amount of matter and antimatter
• When can pair production happen?

  when the photon has an energy greater than the total rest energy (2E), any excess energy is converted into the kinetic energy of the particles
• Strong Interaction exchange particle

  Gluon
• Weak interaction exchange particle

  W boson
• Electromagnetic exchange particle


  Virtual Photon
• Gravity exchange particle


  Gravitation
• Range of the strong interaction

  3x10^-15
• Range of the weak interaction

  10^-18
• Range of the electromagnetic interaction

  Infinite
• Range of gravity


  Infinite
• What is effected by the strong interaction?

  Hadrons only
• What is effected by the weak interaction?

  All particles
• What does the electromagnetic force effect?

  All charged particles
• What does gravitational force act on?

  All particles with mass
• What are the two types of particles?

  Hadrons and Leptons
• What are Hadrons?


  Particles made of quarks
• What are the two types hadron?

  Baryons and Mesons
• What is a baryon made from?

  3 quarks
• What is a meson made from?

  A quark and antiquark pair
• What is the only stable baryon?

  Proton
• What is the only stable Lepton?

  Electron
• are leptons fundamental particles?

  Yes
• What do muons decay into?

  Electrons
• How are strange particles produced?

  Through the strong interaction
• What do Kaons decay into?

  Pions
• Does strangeness get conserved in interactions?

  Yes in the strong interaction.

  Not always in the weak interaction (it can change by -1, 0, or 1)
• what properties must be conserved

  Energy, Momentum, Charge, Baryon number, Lepton number (electron + muon)
• Photoelectric effect


  The emission of electrons from a metal when light shines on the metal