P 7. Particles and nuclear structure Flashcards
Know matter and antimatter
It’s like yin and yang
Tell me about fundamental particles
(totally optional, maybe read it every 10 cards passed)
(or do whatever lol)
Scientists made basic structure of an atom:
consisted of heavy nucleus made of protons and neutrons surrounded by electrons in different energy levels
Three types of forces matching the 3 particles:
gravitational force between masses, electromagnetic forces between the charges and the strong force acting between nucleons
Then some dude tried to find another particle - a particles identical to the electron but with a positive charge. Summin bout a theory that anti-electrons called positrons had to exist
Course Carl detected “positrons” in cosmic radiation so ye ig they do exist. And as theory for neutrons being developed as a fundamental particle, new discoveries were undermining it. (The neutron was not the original building block)
What constituted a fundamental particle?:
Something that cannot be broken down into smaller parts
What are fundamental particles made out of?
Particles are made up of 2 things:
- Light leptons
- Heavy hadrons
We look within…
Define “light” leptons
(2 things)
- Light particles
- They don’t feel strong force
Define “heavy” hadrons
(3 things)
- Heavy particles
- They feel strong force
- Made of quarks
What are the 4 main sub-particles in the particles classification system?
- Leptons
- Hadrons
- Baryons
- Mesons
Show me the whole particles classification system
(u can look at this like every 20 cards lol?)
Leptons
Consists of 3 particles:
- Electron (fundamental?)
- Neutrino
- Others
Hadrons
Consists of 2 particles:
- Mesons (made of 2 quarks)
- Baryons (made of 3 quarks)
Baryons
Consists of 2 other particles:
- Proton (uud)
- Neutron (udd)
Mesons
Consists of 3 other particles:
- π+ = +1 charge
- π0 = 0 charge
- π- = -1 charge
What are the 3 particles Leptons consist of?
- Electron (fundamental??)
- Neutrino
- Others (nice)
What are the 2 particles Hadrons consist of?
Ig made up of how many quarks of each particle?
- Mesons (Made of 2 quarks)
- Baryons (Made of 3 quarks)
What consists of Baryons? 2 things
rq bout their quark number?
Proton and Neutron
They each 3 quarks
What consists of Mesons? 3 things
rq bout their quark number?
Pions:
- π+
- π0
- π-
They each have 2 quarks
Tell me all about matter and antimatter
(huge)
Ever since positron discovery, antiparticles been observed & detected for all known particles
But tbh, we just know it’s the exact opposite type shiii
Particles & anti with its mass & charge
Proton = 1.673 x 10-27 = +1e
Antiproton = 1.673 x 10-27 = -1e
Neutron = 1.675 x 10 -27 = 0
Antineutron = 1.675 x 10-27 = 0
Electron = 9.11 x 10-31 = -1e
Positron = 9.11 x 10-31 = +1e
Neutrino = 0 = 0
Antineutrino = 0 = 0
Most importantly tho, the charge is important here
I’m unsure we need to know their masses as well??
Uhhhhhh idk…
What are these quark particles?
We have quark particles:
u = +2/3
d = -1/3
ū = -2/3
đ = 1/3 (not the correct letter btw, literally gotta be the same as ū)
GIVEN IN DATA BOOKLET
Then we have to state what the other particles are made out of from these quarks.
In addition, only baryons and mesons are made up of quarks.
What quarks are proton made of?
And baryon charge?
uud
+2/3 + +2/3 + -1/3 = -1
What quarks are neutron made of?
And baryon charge?
udd
+2/3 + -1/3 + -1/3 = 0
What quarks are antiproton made of?
And baryon charge?
ūūđ
-2/3 + -2/3 + +1/3 = -1
What quarks are antineutron made of?
And baryon charge?
ūđđ
-2/3 + +1/3 + +1/3 = 0
What quarks are π+ made of?
And baryon charge?
uđ
+2/3 + +1/3 = 1
What quarks are π0 made of?
And baryon charge?
uū/dđ
+2/3 + -2/3 OR -1/3 + +1/3 = 0
What quarks are π- made of?
And baryon charge?
dū
-1/3 + -2/3 = -1
How does π0 have a much shorter lifetime than the other two pions?
It can annihilate itself by electro magnetics
What’s the jig with leptons?
Ones that don’t have quarks
It’s only their own lepton number lol
Leptons:
Electron e-= +1
Neutrino vε = +1
Antielectron e+ = -1
Antineutrino vε = -1
^ the equivalent to line above type shi
STATED IN DATA BOOKLET EXCEPT THEIR ANTI’S
Lepton number of quarks?
0 idiat
What are the 4 forces of nature?
There are 4 types of forces of nature:
- Electromagnetic [?]
- Strong g
- Weak W or ƶ
- Gravity “graviton”
Explain electromagnetic force? (can’t get symbol, reminds me of egyptian typa symbol)
Due to the exchange of photons
Explain strong force? (g)
Due to the exchange of gluons
Explain weak force? (W or ƶ)
Due to the exchange of W and Z particles
Explain gravity force? (“graviton”)
Theorized to be the exchange of gravitons
In-depth detail of gravity force?
(optional and a checker)
Gravity force (all particles)
- Force that keeps the Earth in orbit around the Sun
- Controls the movement of stars and planets
- Extremely weak and can be ignored
- Unless masses of objects involved are extremely large
- So we can ignore it for particle interactions
In-depth detail of electromagnetic force?
(optional and a checker)
Electromagnetic force (all charged particles):
- Relatively strong
- Governs interactions composed entirely of charged particles and photons
- Neutral hadrons will experience this force as they contain charged quarks
- Strength of force = likeliness interaction will occur
- Lifetime decays associated will be shorter
In-depth detail of strong force?
(optional and a checker)
Strong force (quarks):
- The strongest interaction
- Only experienced by quarks and particles composed of hadron quarks
- Responsible for the production of new particles from nucleon-nucleon interactions
In-depth detail of weak force?
(optional and a checker)
Weak force (all particles):
- Much weaker than strong & electromagnetic force
- Only significant in cases where them 2 forces don’t operate
- Weak nature of force reduces probability of the interaction occurring leading to long lifetime decays
- Interactions where neutrinos are involved or quarks change flavour can only take place via weak force
State strength of strong force
1… ig?
State strength of electromagnetic force
1/137
State strength of weak force
x10-6
State strength of gravity force
6 x 10-39
What particles affected by strong force?
(3 things)
- Hadrons
- Quarks
- Gluons
Strongest to weakest between the 4 forces?
- Strong force
- Electromagnetic force
- Weak force
- Gravitational force
What particles affected by electromagnetic force?
- Things with charge
What particles affected by weak force?
(2 things)
- Quarks
- Leptons
What particles affected by gravity force?
- Anything with mass
Range of strong force?
x10-15
(DIAMETER OF A NUCLEUS)
Range of electromagnetic force?
∞
Range of weak force?
x10-18
(0.1% proton diameter)
Range of gravity force?
∞
“The offense” of strong force?
(2 things)
- Attractive or repulsive
- Based on distance
“The offense” of electromagnetic force?
(2 things)
- Attractive for unlike charge
- Repulsive for like charge
“The offense” of weak force?
(3 things)
- Can attract
- Can repel
- Different mechanism[?, dunno the inside reason D:]
“The offense” of gravity force?
Only attractive
Whole summary on 4 forces of nature?
(totally optional)
Strongest to weakest = affected = range = key points?:
Strong g = Hadrons, Quarks, Gluons = diameter of nucleus = Attractive or repulsive based on distance
Electromagnetic y? = Things with charge = infinity range = Attractive for unlike charge, Repulsive for like charge
Weak W/Ƶ = Quarks and leptons = 0.1% proton diameter = Can attract/repel different mechanism
Gravity “graviton” = Anything with mass = infinity range = Only attractive
And apparently more recently, weak and electromagnetic force have been unified into the electroweak force
Summarise how to do decays?
(u absolutely need past paper questions)
Decays:
2 types you’ll be asked:
Beta decay β - it’s an electron and would increase the “atomic number”
Alpha decay α - a “helium”, decrease in mass by 4 and decrease in atomic number by 2 (the atomic number more imp than the mass)
In addition to this, there’ll obviously be the anti version too, so u’d have to do the reverse
What are the 2 decays to learn?
- β- decay
- β+ decay
How to do a β- decay?
(3 changes)
- +1 proton
- antineutrino
- electron
How to do a β+ decay?
- -1 proton
- neutrino
- positron
Summarise how to do conservations?
Conservations:
So for this one, there’ll be 3 laws to be aware of:
charge, baryons and leptons
You’d be told about their numbers in the data booklet however, be very very aware about the anti stuff
You practically gotta remember how many u’s and d’s protons and neutrons and the mesons have since that’s probably the stuff u’d needa learn
What are the 3 laws to be aware of for conservations?
- Charge n°
- Baryon n°
- Lepton n°
Very important, insert sometime how to find the conservation of each laws
Apologise
WE HAVE TIME
Lowkey liked this topic more than any of them here
I stand corrected
In terms of difficulty, revamping is hella long
Still will do it lol
