Step-by-step explanation:
A nuclear reaction is defined as a reaction in which two nuclei combine together to result in the formation of a new nuclei.
When two nuclei combine together then it is known as nuclear fusion. And, when a large nuclei split into two small nuclei then it is known as a nuclear fission reaction.
For example,
As we know that alpha particle is
.
So, when
is subjected to neutron capture followed by alpha emission then products are
along with emission of a positron.