It sounds a bit like alchemy, but researchers have created a pair of matter/antimatter particles using light and gold – but instead of a philosopher’s stone, the team needed a particle collider. The collision occurred on the Relative Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory. A team there breaks the nucleus of a gold atom to create a high-energy photon.
Instead, those photons were used to create a series of electrons and positrons – the antimatter version of electrons. The idea that light can be turned into the matter is based on Einstein’s famous equation, E = mc2. In 1934, physicists Gregory Brett and John A. Wheeler described the hypothetical probability of the collision of light particles to form the first pair of electrons and positrons. As reported in the Physical Review Letter, Star Collaboration has shown that this can be done.
A member of RHIC’s STAR Collaboration Zhangbu Xu said in a statement, “In their research paper, Brett and Wheeler already realized that it was almost impossible to do.” “Lasers didn’t exist yet! But Brett and Wheeler offered an alternative: accelerate heavy ions. And their alternatives are exactly what we’re doing at RHIC.” In this experiment the gold ions are made up of only the nucleus, stripping all its electrons. RHIC can accelerate these gold ions to 99.995 percent of the speed of light before they collide with each other in several strange physics states. However, the most important factor for this experiment is gamma-ray photon production.
Some of these photons can interact with each other, resulting in electron-positron pairs-as predicted about 80 years ago. “Our results provide clear evidence of the direct, one-step creation of object-antimatter pairs from collisions of light, which was originally predicted by Brett and Wheeler,” explained Daniel Brandenburg, who analyzed the data for collaboration.
“Thanks to RHIC’s high-strength heavy ion beams and STAR detectors for greater acceptance and accuracy measurements, we are able to analyze all kinematic distributions, including high statistics, to determine whether experimental results are consistent with actual photon collisions.” A different perspective has shown that in the last few weeks it has been possible to obtain objects and antimatter from light and further investigations into how we can convert energy into the matter will continue.
