1. Basic Nuclear Properties
Static nuclear properties (Time-independent):
Electric charge, radius, mass, binding energy, angular momentum, parity, magnetic dipole moment, electric quadrupole moment, energies of excited states.
Dynamic properties (Time-dependent):
Self-induced (Radioactive decay).
Forced (Nuclear reactions)  cross sections.
The key: Interaction between individual nucleons.
Excited states: atomic intervals ~ eV.
nuclear intervals ~ 104 – 106 eV.
Decays and reactions: Conservation laws and selection rules.
HWc 2 Where to find nuclear data???
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

2. Nuclear Mass (Introduction)
Unified atomic mass unit u based on 12C.
Replaced both physical and chemical amu based on 16O and natural oxygen, respectively (Find conversion factors).
1 u = M(12C)/12 = ……… kg = …………… MeV/c2.
Rest masses
u MeV/c kg
electron ………… …………… ………
proton ………… …………… ………
neutron ………… …………… ………
12C …………… ………
Avogadro’s number .. !! What is the number of atoms in 1 kg of pure 238U?
Mass  Stability. E = mc2. Tendency towards lower energy  Radioactivity.
Neutron heavier than proton  “Free” neutron decays (T½ = ???):
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

3. Nuclear Mass (Introduction)
Nuclear masses measured to high accuracy:
mass spectrograph.
energy measurement in nuclear reactions.
Mass decrement = difference between actual mass and mass number:
Δ = m – A
Δ of parent(s) > Δ of product(s)  radioactivity.
Binding Energy?
Stability?
Fission?
Fusion?
More later ……..
Mass doublet method.
Usually atomic masses are tabulated.
Mass of the atom < ZmH + Nmn.
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

4. The Valley of Stability
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

5. Nuclear Size Depends on probe and relevant physics.
Different experiments give different results  Radius not well defined.
Depends on probe and relevant physics.
Probes should be close to the order of the size of the nucleus ~ m.
Visible light?  much larger.
1 MeV ?  = ?? x m. Interacts with orbital electrons.
Suitable probes: p, n, , e .... Charge distribution. Mass distribution.
All experiments agree qualitatively and somehow quantitatively.
Project ….
 R  A⅓
R = r0 A⅓ with r0 dependent on the method.
Matter distribution  charge distribution. [Recently some halo
nuclei, e.g. 11Li, found]. What is that?
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

6. Nuclear Size HW 4 HWc 3 Experiments show that
t = (2.4 ± 0.3) fm for all nuclei 
t/R  A-1/3
Is surface effect the same for all nuclei?
HWc 3
Compare for A = 4, 40, 120 and 235.
0 = nucleon density near the center.
t = “skin” thickness.
a = thickness parameter.
R = Half-density radius.
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

7. Nuclear Size Why? R  A⅓ 0 decreases with A? No Yes
High-energy e scattering
Light nuclei?
From some experiments….!
Charge distribution: r0 = 1.07 fm. a = 0.55 fm.
Matter distribution: r0 = 1.25 fm. a = 0.65 fm.
Why?
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

8. Nuclear Size 40Ca ….. ….. 59Co ….. ….. 115In ….. ….. 197Au ….. …..
HW 5
Nucleus Z/A Charge density
40Ca … …..
59Co … …..
115In … …..
197Au … …..
Charge radius ~ nuclear radius, even though heavy nuclei have more neutrons than protons. Explain…
Density of ordinary atomic matter ~ 103 kg/m3. Density of nuclear matter
~ 1017 kg/m3.
Neutron stars, 3 solar masses, only 10 km across ….. !!!
Surface effect?
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

9. Short range of nuclear force
Nuclear Size
Three conclusions can be drawn:
Inside the nucleus the density is fairly uniform.
The transitional surface layer is thin.
The central density has a similar value for different nuclei.
Liquid Drop
Short range of nuclear force
Saturation?
Get an estimate for nuclear density and thus inter-nucleon distance.
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).

10. Nuclear Size HW 6 How can we get r0 from the graph?
1 Ci Pu-Be Neutron Source
Neutron
Detector
Absorber
Beam
From Optical Model
Dimensions
Different
targets
HW 6
How can we get r0 from the graph?
Preferably low 
Nuclear and Radiation Physics, BAU, Second Semester, (Saed Dababneh).