Classification ( 2 ) Flashcards
What are the two groups of particles?
- Hadrons
* Leptons
What are leptons?
Leptons are fundamental particles that do not feel strong nuclear force, they interact through the weak interaction, gravitational interaction, and the electromagnetic interaction if charged.
What are Hadrons?
Hadrons are particles that can interact through all four fundamental interactions, chiefly the strong interaction and through the electromagnetic interaction if charged.
How do hadrons decay?
Through the weak interaction
What is the only stable baryon?
Proton
What two groups make up hadrons?
- Baryons
* Mesons
What are baryons?
Baryons are protons and all other hadrons that decay into protons, either directly or indirectly
What are mesons?
Mesons are hadrons that do not include protons in their decay products ( kaons and pions are not baryons ).
What particles make up hadrons?
Quarks and Anti Quarks.
What do baryons decay to?
A proton
What are the anti particles of baryons called?
Anti baryons
What is the baryon number?
Number of baryons in a particle
What is the baryon number of baryons?
+1
What is the baryon number of non baryons?
0
What is the baryon number of anti baryons?
-1
How is the total baryon number affected in an interaction?
The total baryon number in any particle interaction never .
What is the baryon number of mesons?
0
What are the lightest mesons?
Pions
With which force do mesons interact with baryons?
Strong nuclear force.
How do leptons interact with other particles?
Via the weak interaction
How do electrons compare to muons?
- Electrons are stable
* Muons, heavy electrons, are unstable and decay into electrons.
What are the different neutrinos?
- Electron Neutrino
* Muon Neutrino
by which interaction can leptons change into other leptons?
Weak interaction
What is a key feature of leptons?
They cannot break down into non leptons, they are fundamental.
What is a key feature of lepton conservation?
Each lepton number must be counted separately, each different lepton has a lepton number of +1
What occurs in muon decay?
A muon changes into a muon neutrino.
Why are electrons & anti neutrinos created in muon decay?
- Electron created to conserve charge
* Corresponding anti neutrino created to conserve lepton number.
What is the lepton number for leptons?
+1
What is the lepton number for anti leptons?
-1
What is the lepton number for non leptons?
0
