Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Why is Uranium 235 fissionable by thermal
neutrons, but Uranium 238 is not
Introduction
Nuclear Forces
Binding
Energy
Farooq Kyeyune
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
28th , October, 2010
Overview
Why 238 U isn’t
fissionable by
thermal
neutrons.
1
Introduction
Nuclear Forces
2
Binding Energy
3
Liquid Drop Model
4
Nuclear Energy
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Nuclear Fission
Conclusion
5
Conclusion
INTRODUCTION
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What keeps the nucleons together?
BINDING ENERGY
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What is Binding energy?
BINDING ENERGY
Binding Energy per nucleon vs Atomic Mass Number
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
LIQUID DROP MODEL
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What structure do nuclei have?
Treat the nucleus as a dense, spherical liquid drop.
The semi-empirical Mass formula.
B(A, Z) = Other terms +
((−1)Z + (−1)N ) ap
2
A1/2
LIQUID DROP MODEL
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What structure do nuclei have?
Treat the nucleus as a dense, spherical liquid drop.
The semi-empirical Mass formula.
B(A, Z) = Other terms +
((−1)Z + (−1)N ) ap
2
A1/2
LIQUID DROP MODEL
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What structure do nuclei have?
Treat the nucleus as a dense, spherical liquid drop.
The semi-empirical Mass formula.
B(A, Z) = Other terms +
((−1)Z + (−1)N ) ap
2
A1/2
LIQUID DROP MODEL
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What structure do nuclei have?
Treat the nucleus as a dense, spherical liquid drop.
The semi-empirical Mass formula.
B(A, Z) = Other terms +
((−1)Z + (−1)N ) ap
2
A1/2
NUCLEAR ENERGY
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What is nuclear energy?
Is the energy in the nucleus (core) of an atom.
Can be used to make Electricity, Nuclear bombs.
Released through nuclear fusion or fission.
NUCLEAR ENERGY
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What is nuclear energy?
Is the energy in the nucleus (core) of an atom.
Can be used to make Electricity, Nuclear bombs.
Released through nuclear fusion or fission.
NUCLEAR ENERGY
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What is nuclear energy?
Is the energy in the nucleus (core) of an atom.
Can be used to make Electricity, Nuclear bombs.
Released through nuclear fusion or fission.
NUCLEAR ENERGY
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
What is nuclear energy?
Is the energy in the nucleus (core) of an atom.
Can be used to make Electricity, Nuclear bombs.
Released through nuclear fusion or fission.
FISSION OF
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
235
U
LIQUID DROP MODEL FOR FISSION OF 235 U.
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
POTENTIAL ENERGY Vs DEFORMATION
DISTANCE
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
CONCLUSION
Why 238 U isn’t
fissionable by
thermal
neutrons.
Farooq
Kyeyune,
AIMS
Introduction
Nuclear Forces
Binding
Energy
Liquid Drop
Model
Nuclear
Energy
Nuclear Fission
Conclusion
In conclusion . . . We realise that nuclear fission of 238 U is
not possible with thermal neutrons but, the process can be
possible with ’Fast’ neutrons.