Conservation Rules

?

What is conserved?

  • Energy
  • Momentum
  • Baryon Number
  • Lepton Number
  • Charge
  • Strangeness in Stong interactions
  • Strangeness can change by +1, 0 or -1 in weak interactions
1 of 4

Conservation of Energy

  • The total energy in a partical is a combination of the rest mass energy and the kinetic energy
  • Etotal = E0 + Ekin = M0C^2 + 1/2mv^2
  • Kaons decay do not need strangeness conservation as it is decaying via the weak interaction.
2 of 4

Hadron Stability

  • All mesons are unstable and decay quickly
  • The proton is the only stable baryon
  • Neutrons are unstable when they are not within an atomic nucleus with a half life of 611 seconds
3 of 4

Additional Particles

  •  Using only u, d and s quarks you can only make pions and kaons
  • You can make additional baryons by combining sets of three quarks (e.g. uuu, uus, dds, dss etc.)
  • You should be able to write down the subsequent properties of any baryon from its quark components even though they aren't explicitly taught on this course.
4 of 4

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Particle physics resources »