Joseph Thompson

Joseph John Thomson (December 18, 1856 - August 30, 1940) , often known as "JJ", was a British scientist. He was born near Manchester and studied at Trinity College, Cambridge. He became Cavendish Professor of physics in 1884. He married Rose Paget in 1890 and had two children.

He discovered in 1897 that cathode rays (see cathode ray tube) consisted of negatively charged particles, which he called corpuscles, and which were later identified as electrons. The electron had been posited earlier, by G. Johnstone Stoney, as a unit of charge in electrochemistry, but Thompson realised that it was also a subatomic particle, the first one to be discovered.

He received the Nobel prize for physics in 1906 for his work on electric discharges in gases.

He became Master of Trinity College in 1918, where he remained until his death.