Chapter 8
Nuclear Physics – II
8.1 Basic Concepts and Formulae ................................
Nuclear models
Fermi gas model
Total kinetic energy of all protons
EZ=
3
5
ZEZ(max);EZ(max)=K^2
2 M
(
Z
A
)^23
(8.1)
Total energy of all neutrons.
EN=
3
5
NEN(max);EN(max)=K^2
2 M
(
N
A
)^23
(8.2)
whereK=r 0(
9 π
4) (^13)
(8.3)
Shell modelMagic Numbers: 2, 8, 20, 28, 50, 82, 126. Table 8.1 shows the shell
number (Λ) occupation number (Ns) and the Number of neutrons and protons in
various shells (ΣNs) under the spin – orbit coupling scheme.
Table 8.1
Λ Ns ΣNs
5 N′Λ= 44 126
4 N′Λ= 32 82
3 N′Λ= 22 50
32(Λ+1)= 828
2 NΛ= 12 20
1 NΛ= 68
0 NΛ= 22
427