Quarks and Antiquarks

• What are the three most common flavours of quarks?

  Up, down, and strange

  
• What are hadrons primarily made of?

  Different combinations of quarks
• What properties do quarks have?

  Charge, baryon number, and strangeness

  
• How is the charge of a hadron determined?

  By the sum of its quarks' charges
• What is the charge of a proton made up of?

  Two up quarks and one down quark

  
• How is the baryon number of a hadron determined?

  By the sum of its quarks' baryon numbers
• What is the equivalent antiparticle of a quark?

  Anti-quark
• How do anti-quarks differ from quarks?

  They have opposite charges and baryon numbers

  
• What is the baryon number of quarks?

  +1/3
• What is the baryon number of anti-quarks?

  –1/3

  
• What is the strangeness of strange quarks?

  –1
• What is the strangeness of anti-strange quarks?

  +1

  
• What is the quark structure of a K particle with strangeness -1?

  • Kaon is a meson (quark + anti-quark)
  • Contains a strange quark (s)
  • Overall charge of -1 requires anti-up quark (−u)
  • Quark structure: s and −u

  
• What are protons and neutrons made of?

  Three quarks each

  
• What quarks make up a proton?

  Two up quarks and one down quark

  
• What quarks make up a neutron?

  Two down quarks and one up quark

  
• What are mesons made of?

  • A quark and an anti-quark pair
  • Examples: Pions and kaons

  
• What are the types of pions?

  Up and anti-down, anti-up and down
• What are the types of kaons?

  Up and anti-strange, anti-up and strange
• What is the total number of up quarks in 26 protons and 30 neutrons?

  82 up quarks

  
• What quark combinations should be memorized for the exam?

  • Protons: uud
  • Neutrons: udd
  • Pions: up and anti-down, anti-up and down
  • Kaons: up and anti-strange, anti-up and strange