8B. forget the small talk, the surface level ain't much that I care for [COMPLETE] Flashcards
nuclear & particle physics (particle)
What are all particles of matter are made up of?
Made up of either quarks and/or leptons.
What are the 1st generation quarks?
Up and down quarks.
What are the 2nd generation quarks?
Charm and strange quarks.
What are the 3rd generation quarks?
Top and bottom quarks.
What are the 1st generation leptons?
Electron and electron neutrino.
What are the 2nd generation leptons?
Muon and muon neutrino.
What are the 3rd generation leptons?
Tau and tau neutrino.
What is the trend in increasing generations?
Increasing mass.
What are hadrons made up of?
Quarks.
What type of forces do hadrons interact with?
Strong nuclear force.
What are the types of hadrons?
Baryons and mesons.
What are baryons consisting of?
3 quarks.
What are mesons consisting of?
A quark-antiquark pair.
What are the most common baryons?
Protons and neutrons.
What are the most common mesons?
Pions and kaons.
What are quarks discovered in?
Always discovered in pairs or groups of three, never alone.
What charges does all baryons and mesons have?
They all have integer charges.
What is the combination of quarks in a baryon?
3 quarks of either all quarks or all anti-quarks.
What is the difference between the quark content of a meson and its anti-particle?
The quark in the meson becomes its anti-quark in the anti-particle.
What are electrons?
Stable leptons.
What are muons?
Heavy unstable leptons (eventually decays to an electron).
What are taus?
Heaviest least stable lepton.
What are antiparticles
Each particle has a corresponding antiparticle with identical mass and opposite charge, baryon and lepton numbers.
What is a fundamental particle?
has no internal structure / not made up of other particles
What is the last quark to be discovered?
Top
What is the lightest quark?
up
What is the heaviest quark?
top
What are leptons?
They are a group of fundamental (elementary) particles.
What are leptons made up of?
They are not made up of anything else.
How does leptons interact with other particles?
Via weak, electromagnetic or gravitational interactions. They do not interact via the strong nuclear force.
What are the most common leptons?
Electrons, electron neutrinos, muons, and muon neutrinos.
What is the difference between a muon and an electron?
Muon is 200x more massive than electrons.
What is the mass of an electron?
0.0005u.
What is the mass of a muon?
0.11u.
What are neutrinos?
They are the most abundant leptons in the universe. They have no charge and negligible mass.
What are photons?
They are a group of atoms which mediate the electromagnetic interaction.
What charge do photons have?
They have no charge/uncharged.
What is the mass of photons?
They have no mass.
What are photons sometimes called?
Exchange/gauge bosons.
Why are photons sometimes called exchange/gauge bosons?
They mediate one of the fundamental forces (electromagnetism).
What is the photon an exchange particle for?
Electromagnetic force.
What type of “particle” is a photon?
A boson.
What were the first 4 quarks discovered?
The up, down, strange and charm quarks.
How was the symmetry of the standard model used?
It was used to predict a third generation of particles.
What is neutron decay?
Neutrons are unstable when outside the nucleus so it decays to a proton via beta decay.
Why did it take a long time to find experimental evidence for the top quark?
large mass, needs a lot of energy
What do all matter particles have?
An antimatter counterpart.
What are the similarities between matter particles and antimatter particles?
Almost identical except for one thing.
What is the difference between matter particles and antimatter particles?
They have the opposite electric charge of each other.
What two things matter particles and their antimatter counterpart have in common?
Identical mass and rest mass energy.
What is always conserved when particle interaction equation?
Quantum numbers.
What quantum numbers are conserved in particle interaction?
Charge (Q), baryon number (B), and lepton number (L).
What has a charge Q = +1 in particle interactions?
Protons and positrons.
What has a charge Q = -1 in particle interactions?
Electrons + other leptons.
What is the baryon number?
The number of baryons in an interaction.
What has a baryon number B = +1 in a particle interaction?
Baryons like protons and neutrons.
What has a baryon number B = -1 in a particle interaction?
Anti-baryons.
What has a baryon number B = 0 in a particle interaction?
Anything that is not a baryon, e.g. leptons and mesons.
What has a baryon number B = +1/3 in a particle interaction?
Quarks.
What has a baryon number B = -1/3 in a particle interaction?
Anti-quarks.
Why are baryons made up of only all quarks or anti-quarks, not a mixture?
So, the baryon number adds up to an integer. A mixture would not produce an integer baryon number.
What are baryons made up of?
Only quarks.
What are anti-baryons made up of?
Only anti-quarks.
What is the lepton number?
The number of leptons in an interaction.
What has a lepton number L = +1 in a particle interaction?
Leptons like electrons and neutrinos.
What has a lepton number L = -1 in a particle interaction?
Anti-leptons.
What has a lepton number L = 0 in a particle interaction?
Not leptons.
What things must be conserved for a possible particle interaction (conservation laws)?
Charge, baryon number, lepton number, energy(or mass-energy) and momentum.
What happens if the conservation laws for particle interactions are not met?
The interaction is impossible/cannot occur.
What values can Q, B and L numbers can take?
Discrete values.
What to do to check if a particle interaction is possible?
Check if each quantum number is equal on both sides of the equation. If one of them is not equal, then the interaction cannot occur.
What are the 4 gauge bosons?
Gluons, photons, gravitons, bosons.
What is the symbol for photons?
γ
What is the symbol for gluons?
g
What is the symbol for bosons?
W & Z.
What are the 4 fundamental forces?
Gravitational, electromagnetic, weak nuclear and strong nuclear forces.
What are the fundamental forces carried by?
Gauge bosons.
What particles experience gravitational force?
All particles.
What is the range of gravitational force?
Infinite.
What gauge boson is gravitational force carried by?
G, gravitons. [hypothetically]
How strong is the gravitational force on particles?
Very weak, negligible unless in the context of larger objects like planets and stars.
What particles experience weak nuclear force?
All particles.
What is the range of weak nuclear force?
Very short, 10-18 m.
What gauge boson is weak nuclear force carried by?
W & Z bosons.
When is weak nuclear force significant?
When electromagnetic and strong nuclear interactions do not operate.
What particles experience electromagnetic force?
All charged particles and neutral hadrons as they are composed of quarks.
What is the range of electromagnetic force?
Infinite.
What gauge boson is electromagnetic force carried by?
γ, photons.
What particles experience strong nuclear force?
Quarks and particles made of quarks.
What is the range of strong nuclear force?
Short, 10-15 m.
What gauge boson is strong nuclear force carried by?
g, gluons.
What is the symbol for an up quark?
u
What is the symbol for a down quark?
d
What is the symbol for a charm quark?
c
What is the symbol for a strange quark?
s
What is the symbol for a top quark?
t
What is the symbol for a bottom quark?
b
What is the symbol for an anti-quark?
Its normal quark symbol with a bar on the top.
What does the symbol “u” represent?
A up quark.
What does the symbol “d” represent?
A down quark.
What does the symbol “c” represent?
A charm quark.
What does the symbol “s” represent?
A strange quark.
What does the symbol “t” represent?
A top quark.
What does the symbol “b” represent?
A bottom quark.
What is the charge for an up quark?
+2/3 e
What is the charge for a down quark?
-1/3 e
What is the charge for a charm quark?
+2/3 e
What is the charge for a strange quark?
-1/3 e
What is the charge for a top quark?
+2/3 e
What is the charge for a bottom quark?
-1/3 e
What is the charge for an anti-quark?
Multiply the original quark’s charge by -1.
What is the symbol for an electron?
e-
What is the symbol for a muon?
μ-
What is the symbol for a tau?
τ-
What is the symbol for an electron neutrino?
Ve
What is the symbol for a muon neutrino?
Vμ
What is the symbol for a tau neutrino?
Vτ
What is the charge of a lepton?
-1e
What is the charge of neutrinos?
No charge.
What is the relative charge of an electron?
-1
What is the relative charge of a positron?
+1
What is the relative charge of a proton?
+1
What is the relative charge of an anti-proton?
-1
What is the relative charge of a neutron?
0
What is the relative charge of an anti-neutron?
0
What is the relative charge of a neutrino?
0
What is the relative charge of an anti-neutrino?
0
What is the symbol for a positron?
e+
What is the symbol for a proton?
p
What is the symbol for a neutron?
n
What does the symbol “e+” represent?
A positron.
What does the symbol “p” represent?
A proton.
What does the symbol “n” represent?
A neutron.
What is the quark content of a proton?
uud
What is the quark content of a neutron?
udd
What is the quark content of a K+?
u ŝ
What is the quark content of a K?
d ŝ
What is the quark content of a K-?
s û
What is the quark content of a π+?
u antidown
What is the quark content of a π?
u û
OR
d antidown
What is the quark content of a π-?
d û
What is the quark content of a lambda particle?
u d s
Why are collisions high energy?
Energy required to overcome electrostatic repulsion. Since particles move fast the energy/momentum must be high, shorter de broglie wavelength.
Why are only a low proportion of decays detected?
- emmisions in all directions
- some emitted particles may be absorbed by the material in the sample
- some emitted particles may be absorbed by the window
- some pass through the detector
What does firing electrons at a hydrogen target tell us?
- proton is not uniform, it has some empty space since some electrons passed through
- made up of smaller particles called quarks
What is the atomic process that produces emission spectra?
electron drops down energy levels and de-excites releasing energy
