Physicist Carl David Anderson discovered antimatter in 1932 in a magnetic cloud chamber at the California Institute of Technology, Pasadena, CA, USA. The cosmic rays in the chamber left a trail that curved in the wrong direction. Particles with the mass and energy of an electron, but with a positive charge rather than a negative charge. Anderson gave the particle the name “positron.” When a positron contacts a normal electron, both are annihilated, releasing a flash of energy.
Carl David Anderson
Pasadena, CA, USA
- Positron – Wikipedia
Anderson did not coin the term positron, but allowed it at the suggestion of the Physical Review journal editor to whom he submitted his discovery paper in late 1932. The positron was the first evidence of antimatter and was discovered when Anderson allowed cosmic rays to pass through a cloud chamber and a lead plate.
- California Institute of Technology – American Physical Society
In 1932, Anderson, then a postdoc in the physics department, was … be produced by a particle “carrying a positive charge but having a mass of the same order of … Anderson’s remarkable discovery of antimatter, and subsequent discoveries of …
- This Month in Physics History, August 1932: Discovery of the …
August 1932: Discovery of the Positron. … The energy produced is insufficient to form even the lightest particle and antimatter and emerges instead as two …
- matter–antimatter asymmetry – Antimatter | CERN
The insight opened the possibility of entire galaxies and universes made of antimatter. But when matter and antimatter come into contact, they annihilate …
- Carl Anderson discovers the positron | timeline.web.cern.ch
In 1932 Carl Anderson, a young professor at the California Institute of … After nearly a year of effort and observation, he decided the tracks were actually anti electrons, each produced alongside an … For discovering the positron, Anderson shared the 1936 Nobel prize in physics with Victor Hess. … The story of antimatter.