What is Bohr's theory of compound nucleus ?

1 Answer
Mar 1, 2018

Bohr proposed the compound nucleus theory in which a nuclear fission takes place in two stages :

1) Formation of the compound nucleus
2) Decay of the compound nucleus

They are explained below.

Explanation:

1) Formation of the compound nucleus :

When a high energy projectile such as a neutron collides with a nucleus, a compound nucleus is formed wherein, the neutron is absorbed by the initial nucleus.

2) Decay of the compound nucleus :

As the total energy of the projectile is transferred to the compound system, the compound nucleus is thus in an excited state. The average increase in energy per nucleon is not enough to free it from the nucleus but, there is a large probability for the compound nucleus to split into fragments each containing multiple nucleons. When this happens, the nuclear fission is completed.

It may also be remarked that probability of decay into a specific set of products is assumed to be independent of formation of the compound nucleus. This is known as the Bohr's independence hypothesis.