Particle Physics Flashcards
What does Z refer to?
Proton number
What does A refer to?
Mass number
What are Isotopes?
Isotopes are variations of elements with the same Z number and different A number
What can Isotopes do?
They can tell you the age of dead organic matter. Carbon-14 is in the atmosphere and is absorbed by every living thing, but once that thing no longer lives, the amount of carbon-14 decreases through half life. (Carbon-14 is radioactive.)
What is specific charge?
Specific charge(C/kg) = Charge(C)/Mass(kg)
Strong Nuclear Force
- Holds nucleons together. (0.5-3fm)
- Stronger than Electrostatic force up to 3 fm, but quickly falls to 0 after.
- Only affects Hadrons.
Alpha emission
- Occurs in large nuclei
- Large nuclei is too big for strong force to keep them stable
- Alpha particle = -2z - 4a
- Short range
Beta minus decay
- Neutron rich nuclei.
- Beta particle: +1z
- Has antineutrino alongside it.
Antineutrino
- Carries remaining energy in beta minus decay equation.
- Neutral charge
- Almost zero mass. (Known it has mass because it can oscillate through different flavours)
Frequency
Frequency(Hz) = Speed of light(m/s)/Wavelength(m)
Energy
Energy(J) = Planck’s constant(Js) × Frequency(Hz)
Energy(J) = (Planck’s constant(Js) × Speed of light(m/s))/Wavelength(m)
E =mc^2
Einstein’s theory of relativity.
It means matter can be made from energy. In fact, the rest energy of a particle is just the energy equivalent of the mass of that particle.
Pair production
An antiparticle-Particle pair is produced from a high energy photon that has enough energy to form an antiparticle and particle pair.
Annihilation
When an antiparticle and particle meet, they smash and die. Usually, electron and positron are used, forming two photons.
However one photon can be a product if there is something else to carry the momentum. (Positronium decay in an external field.)
And high energy annihilation can form more than two.
Gauge bosons
Particles that carry momentum, causing (non-contact) forces to happen.
Virtual Photon
From the electrostatic force, only affects charged particles.
Very little mass, allowing for electrostatic force to have indefinite range.
Doesn’t obey the energy-momentum relation.
W(plus or minus) bosons
It’s tied to the weak force and it affects all particles.
Pions (+,0,-)
Strong force and only affects hadrons.
Draw some diagrams of these exchanges.
You did it wrong.
Hadrons
Affected by the strong force.
- Baryons and Mesons
Leptons
Electron, Muon, Tau.
Positron, anti-Muon, anti-Tau.
Neutrino (E,M,T)
Anti-Neutrino (E,M,T)
Baryons
Proton: The most stable baryon.
Neutron: Decays into a proton when outside of a nucleus.
Mesons
Antiparticle-particle pair
Pions: Idk
Kaons: Weird lil shits, absolutely strange.
