Particle And Nuclear Phsyics Flashcards
State quark composition of Baryon
qqq
What is the quark composition of a K - meson
Ūs
What is the equation of electron capture
P+e-~n+Ve
Quark structure of K^0
D š
Quark structure of proton
uud
Quark structure of neutron
udd
Charge of pion +
+1
What is a sigma+ particle and what’s its charge and number
Baryon with Baryon number +1 and charge +1
Give one property of an antiparticle that is same for its corresponding particle and one difference
Same rest mass energy
Different charge
Name two baryons
Proton
Neutron
State one characteristic of a strange particle that makes it different from a particle that is not strange
Has a strange quark
Give one difference between negative muon and an electron
Different rest mass Same charge (negative )
Give a difference between hadron and leptons
Leptons do not feel strong force
What are the differences between mesons and baryons
Baryons made from 3 quarks whereas mesons is a quark antiquark pair
Baryon number is +1/-1 mesons is 0
What property defines a hadron
Feels the strong force
What is the exchange particle in the strong, weak and electromagnetic force
Electromagnetic- photon
Strong force - gluon
Weak force - w+/w-
What is an isotope
Forms of the same element that have the same number of protons but a different number of neutrons
What is the nature of an alpha particle
2 protons , 2 neutrons
What is the sigma + particle and what does it contain
It is a baryon with 3 quarks which is affected by the weak force and will eventually decay into a proton
Name a force that acts between the up quark and an electron . How does this operate
The weak force uses a W+/- exchange particle to transfer energy . This then leads to the creation of a new particle .
Explain why two photons are formed instead of a single photon when helium nucleus annihilates with an anti helium nucleus
Momentum is conserved
So need two photons travelling in different directions
What is decay of a neutron equation
N~p+e-+Ve with hat
What is meant by specific charge
Ratio of charge to mass of nucleus
Measured in Ckg-1
Lepton number of electron and positron
e- = 1 e+=-1
Lepton number of ve with hat
-1
Charge of ve and ve with hat
Ve = +1
Ve with hat = -1
What is the k0 and how does it decay
It is a meson with a strange quark so decays with the weak interaction
Which constituent of an atom has the largest specific charge
Electron
Why is there a minimum energy of the y photon for this conversion to take place in Pair production
What will happen if y photon has slightly more energy
To provide enough energy for the rest mass
Any extra energy will provide the particles with extra kinetic energy
What is the quark structure of anti K0 meson
D with hat s
Pion + quark structure
U D with hat
Pion- quark structure
D U with hat
Pion 0 quark structure
Uū or dd with hat
Kaon + quark structure
Uš
Sigma - and sigma 0 strangeness
-1
What can the kaon decay into
Pions
What is fundamental about the photon
No charge
Massless
What is meant by electron capture
An atomic electron that interacts with a proton in the nucleus via the weak interaction
What is equation for k- meson decay
K-~ pi0+e-+v with hat
What is the difference between B+ and B- decay
In beta+ decay, a proton in the nucleus becomes a neutron and spits out a positron and a neutrino.
In beta- decay, a neutron in the nucleus becomes a proton, and spits out an electron and an anti-neutrino.
How does the nucleon and proton number change in Alpha decay
nucleon- -4
proton- -2
How does the nucleon and proton number change in Beta decay
nucleon- 0
proton- +1
Describe how the strong nuclear force and two nucleons varies with separation of the nucleons quoting suitable values for seperation
repulsive from 0-0.5fm
attractive from 3fm
Repulsive after that
What will likely happen to a positron shortly after its emission during pair production
Meets and electron and annihilates to produce two more photons
What particle is produced when a muon decays
Electron + an electron antineutrino + muon neutrino
What happens when a particle meets its corresponding anti-particle
They annihilate each other
This means that the total mass of the particle is converted into energy, in the form of two gamma ray photons
Two gamma photons are always produced during particle-antiparticle annihilation in order to conserve momentum
What occurs in pair production
Opposite to annihilation
In this process, a photon with enough energy can interact with a large nucleus and be converted into a particle-antiparticle pair
In order to create this particle-antiparticle pair, the photon must have enough energy to create both particles
