Collider would convert photons into electrons and positrons
A proposed experiment may soon transform particles of light into matter.
Oliver Pike, a plasma physicist at Imperial College London, typically works on nuclear fusion — a process that converts matter into energy and not vice versa. But he and his colleagues laid out plans for a device that would use a key piece of fusion equipment to convert light, a form of energy, into particles with mass. It would do so by smashing photons together to create electrons and their antimatter counterparts, positrons. Physicists have never observed this process in the lab.
Detailed May 18 in Nature Photonics, the design relies on a hohlraum, a small metal cylinder that holds hydrogen fuel in laser fusion experiments (SN: 4/20/13, p. 26). Heating a hohlraum with a laser produces a dense field of X-ray photons inside. Pike’s