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Pair production and antimatter

In 1932 Carl Anderson discovered the positron.

The positron is a particle of antimatter and it was the first known particle of antimatter to be found. It has the same mass as an electron but a positive charge.


A high-energy gamma ray passing close to the nucleus of a heavy atom can turn into two particles – an electron (matter) and a positron (antimatter).

When a particle meets an antiparticle they destroy each other producing a flash of energy – usually gamma rays.

Electrons and positrons annihilating each other have been seen in the lab.
 
 
© Keith Gibbs