Particles Flashcards
Proton number= Z
Mass number=A
Chemical symbol= X
A \/
Z /\
What is a nuclide?
Type of nucleus
Specific charge =
Q/m
Unit for specific charge
Ckg^-1
Specific charge of nucleus
(Zxe)/nuclear mass
Specific charge of ion
(Change in number of electrons x e)/nuclear mass including remaining electrons
Strong nuclear force (between protons)
-has a very short range
-attractive from 0.5-3 fm
-repulsive when <0.5fm
Electrostatic force
-very long range
- obeys the inverse square law
-is repulsive between two like particles
-attracts opposites
Strong nuclear and electrostatic combined
-repulsive up to 0.5 fm
- attractive to about 2 fm
-repulsive but nearing zero as distance increases past 3 fm
Detect radiation with
-cloud chamber
-spark counter
-Geiger-muller counter
Alpha emission
Beta-
Beta+
X-> Y+α
X-> Y+(-)β+ antineutrino
X-> Y+(+)β+ neutrino
Electron capture leads to neutrino or antineutrino?
Neutrino
Annihilation
Annihilation occurs when a particle and corresponding particle meet, their mass is converted into energy in two photons
Energy of photons in annihilation
hf= rest mass/energy + kinetic energy
Pair production
When a single photon interacts with a nucleus of an atom, it’s energy may be converted into a particle antiparticle pair. To conserve momentum the photon needs to interact with a particle.
