Antimatter particle discovered in 1932
Positrons were first predicted by Paul Dirac in 1928 and later discovered experimentally in 1932.
A positron is the antimatter counterpart of an electron, with the same mass but opposite charge. Positrons are commonly used in medical imaging techniques such as positron emission tomography (PET) scans. Positrons are produced in natural radioactive decay processes and in particle accelerators. Positrons can annihilate with electrons, releasing gamma rays in the process. Positrons have applications in materials science for studying defects in crystals. Positrons play a role in astrophysics, helping scientists understand phenomena like black holes and neutron stars. Positrons have been used in experiments to study fundamental interactions in particle physics, such as the weak force.