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Hello, in 1932 in a Cambridge laboratory,

James Chadwick discovered the neutron,

one of the building blocks of the atomic nucleus.

It was a crucial stage in the development of nuclear physics.

Scientists quickly so that neutrons were ideal for firing into an

and into an atom's nucleus.

That made the nucleus disintegrate and released huge amounts of energy.

The popular term was splitting the atom and it captured the public imagination.

All the more so when in the following decade it led to the atomic bomb.

In the last 70 years further study of the neutron has shown its applications in

medicine, industry, energy and technology. A deeper understanding of the

neutrons reveals fascinating details of the origins of life of all matter and of the universe.

With me to discuss the neutron R Val Gibson, professor of high energy physics at the University of Cambridge and Fellow of Trinity College.

Andrew Harrison, Chief Executive Officer of Diamond Light Source and Professor In Chemistry at the University of Edinburgh,

and Frank Close, Professor Emeritus of Physics at the University of Oxford.

To start with you, Frank Close, what is a neutron?

Well the neutron is one of the two basic constituents of the atomic nucleus, along with the proton.

The proton is positively charged and its electrical charge provides the electrical

forces that hold atoms together and ultimately enables chemistry and

biology to happen. The neutron is electrically neutral, hence its name, so it doesn't

...