8.8 Summary Notes - The Standsrd Model Flashcards
What is the standard model?
An attempt to organize the hundreds of different subatomic particles. It reduces the hundreds of seemingly different particles to a few fundamental particles and describes the interactions (forces between them). The standard model postulated three classes of particles: quarks, leptons, and bosons.
Quarks
Relatively heavy particles that have fractional charges. (Less than the elementary charge). They cannot be isolated.
What makes up protons and neutrons?
Combinations of quark.
What quarks make up a proton?
Up, up, down
What quarks make up a neutron?
Up, down, down
Leptons
Much lighter particles than quarks (have mass but no internal structure)
~ electrons and neutrinos
Bosons
Particles that are exchanged between quarks and leptons to produce the fundamental forces.
~ protons
Strong force definition and range
The force that holds the nucleus together. Nuclear sizes.
Electromagnetic force definition and range.
The force of attraction or repulsion between charged particles. Infinite
Weak force definition and range.
The force that allows the transmutation of quarks; involved in radioactive decay. Nuclear sizes
Gravity force definition and range.
The force responsible for the attraction of two masses. Infinite
What is the order of relative strength from strongest to weakest.
Strong, electromagnetic, weak, gravity
What are all the conservation laws that subatomic interactions obey in nuclear decay and high energy collisions?
Momentum, charge, mass-energy, nucleon number (atomic mass)
Marat Gell-Mann
Built the system of fundamental particles
Mesons
Unstable particles made of first generation quark-antiquark pairs that are lighter than neutrons and protons.
