Baryons

• What is the baryon number denoted as?

  B

  
• What does the baryon number indicate in an interaction?

  The number of baryons in an interaction
• What baryon number do baryons have?

  B = +1

  
• What baryon number do anti-baryons have?

  B = -1

  
• What baryon number do particles that are not baryons have?

  B = 0

  
• Is baryon number a conserved quantity in interactions?

  Yes, it is conserved in all interactions
• Why is baryon number important in interactions?

  It indicates whether an interaction can occur
• What is the baryon number of up, down, and strange quarks?

  Each has a baryon number of $\frac{1}{3}$
• What is the baryon number of anti-up, anti-down, and anti-strange quarks?

  Each has a baryon number of $-\frac{1}{3}$
• What are baryons made up of?

  All quarks
• What are anti-baryons made up of?

  All anti-quarks
• Why are there no baryons with a combination of quarks and anti-quarks?

  It would result in a non-integer baryon number
• What is the most stable baryon?

  The proton
• Why is the proton considered the most stable baryon?

  It has the longest half-life of any baryon
• What does radioactive decay involve?

  Heavier particles decaying into lighter particles
• What would happen if the proton decayed?

  It would violate baryon number conservation
• What is theorized about the proton's half-life?

  It is around $10^{32}$ years
• How is baryon number conserved in beta-minus decay?

  1. Write the equation: $n \rightarrow p +$$e^- +$$\overline{\nu}_e$
  2. Determine baryon number:

  • Left side: 1 (neutron)
  • Right side: 1 (proton) + 0 (electron) + 0 (antineutrino)

  1. Conclusion: Total baryon number is equal, hence conserved.
• What is the total baryon number in the beta-minus decay equation?

  1 on both sides
• What are the key properties of baryons and anti-baryons?

  • Baryons: B = +1, made of quarks
  • Anti-baryons: B = -1, made of anti-quarks
  • Non-baryons: B = 0
  • Baryon number is conserved in interactions