He received his secondary school education in Manchester where a special aptitude for mathematics and science soon became apparent.
Chadwick received a First Class Horns Degree in 1911 from Victoria University of Manchester and his external examiner being J.J Thomson, discoverer of the electron.
Chadwick earned his Master of Science degree in 1913 and PhD from Cambridge in 1921. In 1921 he became a fellow of Gonville and Caius College, Cambridge and two years later was appointed assistant director of radioactive research at the Cavendish Laboratory.
The discovery of the neutron was made in 1932. Chadwick knew that when α-particles from polonium hit beryllium foil, very penetrating radiation was emitted. He took three years for Chadwick to find a way to detect the presence of any neutrons he created in this way. He used a strong electrical field to deflect α-particles.
Chadwick proved that the radiation consisted of uncharged particles, each of mass about the same as a proton. In other words, Chadwick showed that the radiation was composed of high-speed neutron.
The existence of neutron was predicted by Rutherford in a 1920 lecture, and by mid 1920s, Chadwick was obsessed with the search for Rutherford’s uncharged proton-electron.
Chadwick’s discovery of the neutron not only explained the hitherto unresolved problem of just what particles composed the nuclei of atoms but also gave a powerful tool to explore the nature of these nuclei.
Discovery of neutron by James Chadwick (1891-1974)
