1.7 Particles and Nuclear Structure Flashcards
What are the two groups of elementary particles?
Quarks and Leptons
Are quarks high or light weight particle’s?
They are high mass particles
Are leptons high or light weight particle’s?
They are Light Weight particles
What are the two types of leptons
Electrons, Electron Neutrino
Quarks are either … type or … type
Up
Down
Have Quarks ever been seen alone?
No
Baryons are made of … quarks
3
Mesons are made of a pair of … and …
Quarks
Anti-quarks
Baryons and Mesons are types of …
Hadrons
For each particle that exists there is an … particle
Anti
Antiparticles have the same … but opposite …
Mass
Charges
Up quarks have a … charge
+2/3
Down Quarks have a … charge
-1/3
Anti-up quarks have a … charge
-2/3
Anti-down quarks have a … charge
+1/3
When quarks form a group of three they are called …
Baryons
What are the four combinations of up and down quarks?
uud
udd
uuu
ddd
uud name and charge
Proton, +1
udd name and charge
Neutron delta, 0
uuu name and charge
plus plus, +2
ddd name and charge
delta minus, -1
Antiparticles are represented by a …
small bar above the symbol
Mesons must be made of a … and a …
Quark
Anti-Quark
For first generation mesons they are known as … or …
Pi mesons
Pions
What is the combination of quarks and anti-quarks for a pi plus meson?
_
du
What is the charge for a pi plus meson?
1+
What is the combination of quarks and anti-quarks for a pi minus meson?
_
ud
What is the charge for a pi minus meson?
-1
What is the combination of quarks and anti-quarks for a pi zero meson? 1
_
uu
What is the charge for a pi zero meson?
0
What is the combination of quarks and anti-quarks for a pi zero meson? 2
_
dd
What is the charge for a pi zero meson?
0
Can leptons exist on their own?
Yes
Each lepton is given what?
A lepton number
Any particles that are not leptons have a lepton number of …
0
Electrons lepton number is?
1
Electron neutrinos number is?
1
Anti-electrons number is?
-1
Electron Anti-neutrinos number is?
-1
What are the three conservation laws that apply to decay reactions or collision reactions?
Conservation of Momentum
Conservation of Mass-Energy
Conservation of Charge
In any interaction between particles in a system the baryon number in the system must …
Not change
In any interaction between particles in a system the lepton number in the system must …
Not change
What are the four kinds of forces that can be involved in a reaction?
Gravitational Force, Weak Force, Electromagnetic Force, Strong Force
Weak forces
Effect all particles, Range is very short, very weak force, Involves Neutrinos and change in quark flavour, slowest interaction time x10-12s
Electromagnetic Force
Effects charged particles, Range is infinite, Stronger than weak forces, Involves photons and the particles interacting have a charge, middle interaction time 10-17s
Strong Forces
Effects only quarks, Range is short, The strongest interaction, Only involves hadrons and is the fastest interaction time 10-23s
