used in materials research to detect variations in density, defects, displacements, or even voids, within a solid material. See also Beta particle Buffer-gas trap List of particles Positronium Positronic brain References External links What is a Positron? (from the Frequently Asked Questions :: Center for Antimatter-Matter Studies) Website about positrons and antimatter Positron information search at SLAC Positron Annihilation as a method of experimental physics used in materials research. New production method to produce large quantities of positrons Website about antimatter (positrons, positronium and antihydrogen). Positron Laboratory, Como, Italy Website of the AEgIS: Antimatter Experiment: Gravity, Interferometry, Spectroscopy, CERN Synopsis: Tabletop Particle Accelerator ... new tabletop method for generating electron–positron streams. Antimatter Electron Positron Elementary particles Leptons Quantum electrodynamics