This document provides an introduction to basic nuclear physics concepts. It defines key terms like atomic nucleus, nucleons, nuclides, isotopes, isobars, isotones, and isomers. It explains how to calculate the number of neutrons in a nucleus and provides examples of nuclear classification. The document also outlines general nuclear properties such as size, mass, density, and charge. It concludes with some applications of nuclear physics such as electric power generation, national security, medical diagnosis and treatment, radioactive dating, and household uses.

1. P.RAMYA M sc Mphil.,
DEPARTMENT OF PHYSICS

2. BASICS OF NUCLEAR
PHYSICS

3. INTRODUCTION
 Atomic nucleus was discovered in 1911 by
Rutherford.
 Size of the nucleus is 10-14 meter in diameter.
 All atomic nuclei are made up of elementary
particles called protons and neutrons.
 Proton has positive charge of the same
magnitude as that of on electron.
 Neutron is electrically neutral.

4. • Proton and neutron are the two different charge
states.
• That states are called nucleon.
• Species of nucleus known as nuclide.
• It is represented by ZXA
Z is the atomic number.
A is the mass number.
X is the chemical symbol of species.

5. HOW TO FIND OUT THE
NUMBER OF NEUTRONS
• N= Number of neutrons = A-Z
For example 17cl35has
Z=17 Protons, A= 35 nucleons and
N=35-17= 18 neutrons

6. CLASSIFICATION OF NUCLEI
It can be classified as follows
 Isotopes
 Isobars
 Isotones
 Isomers
 Mirror nuclei
Isotopes
Isotopes are nuclei with the same atomic number Z but different mass number A.
Example 14Si28
14 Si29
Isobars
Isobars are nuclei with the same mass number A but different atomic number Z.
Example 8 O
16
, 7 N
16

7. • ISOTONES
Nuclei with an equal number of neutrons.
For example: 6c14, 7N15, 8o16
• ISOMERS
There are atoms, which have the same Z and same A, but differ from one another in their nuclear
energy states.
• Mirror nuclei
nuclei having the same mass number but with the proton and neutron number interchanged.
For example: 4Be7 (Z=4 and N=3)
3Li7 (Z=3 and N=4)

8. GENERAL PROPERTIES OF NUCLEUS
• Nuclear size
Rutherford work on the scattering of α – particles showed that the means
radius of an atomic nucleus is of the order of 10-14 m to 10-15 m
• Nuclear mass
Assumed Nuclear mass = Zmp + Nmn
real nuclear mass < Zmp + Nmn
Zmp + Nmn – real nuclear mass = Δm

9. • Nuclear density
• The nuclear density ρN can be calculated from =nuclear mass/ nuclear volume
Nuclear charge
The charge of the nucleus is due to the protons contained in it. Each proton
has a positive charge1.6×10-19 C.

10. • Electric power generation (nuclear fission / fusion reactors)
• National Security (nuclear weapons stockpile)
• Medical Diagnosis (PET, MRI) cancer treatment with proton or heavy-ion
beams
• Radioactive dating (geology, archeology)
• Household (smoke detectors, americium-241 α-decay)
APPLICATION