Gamma rays can only be detected by sensors made of dense metals and takes over six feet (1.8 meters) of concrete to block.

Keywords Wilhelm Röntgen, X-rays, cathode rays, fluorescence, Henri Becquerel, uranium, radioactivity, Marie Curie, polonium, radium, Ernest Rutherford, alpha rays, beta rays, gamma rays ...

After emitting an alpha or beta particle, the nucleus will often still be ‘excited’ and will need to lose energy. It does this by emitting a high energy electromagnetic wave called a gamma ray.

Neutrons are relatively massive particles that are one of the primary constituents of the nucleus. They are uncharged and therefore do not produce ionization directly. But their interaction with the ...

By determination of the end-points of the distributions, a rough measure is given of the energy of the gamma-rays. Recently Jordan and Bell2 have published some measurements of that kind.