Leptons Flashcards
What are leptons?
• Fundamental Particles and antiparticles that do not interact through strong interaction ( they do not feel strong nuclear force ).
How do leptons interact?
- Weak interaction
- Gravitational Interaction
- Electromagnetic Interaction, if they are charged.
How do leptons interact with other particles?
Via weak interaction
What are the different leptons?
- Muon
* Electron
What do Muons decay into?
Ordinary electrons.
What are the two types of neutrino for leptons?
- Muon-neutrino
* Electron-neutrino
What are neutrinos?
Particles with zero or almost zero mass, and zero electric charge.
How do leptons become other leptons?
Through weak interaction.
How are leptons produced/annihilated?
Particle-antiparticle interactions
What is the lepton number?
- Number of leptons, each lepton has a number of +1.
- There are two types of lepton numbers, electron and muon.
- These different lepton numbers must be counted separately.
What happens in an interaction between a lepton and a Hadron?
- A neutrino or anti-neutrino can change into or from a corresponding charged lepton.
- An electron neutrino can therefore interact with a neutron to produce a proton and an electron.
- An electron neutrino and a neutron can not change into an anti-proton and a positron.
Why can an electron neutrino and a neutron not change into an anti-proton and a positron?
The lepton number is not conserved:
Ve + n > (anti)P + e+
Lepton number of +1 in the left, Lepton number of -1 on the right, no conservation.
What is a rule for all lepton interactions?
Both types of lepton number must be conserved in any change.
What is the lepton number for anti-leptons?
-1
What is the lepton number for leptons?
+1
