Although there were only about nine of them, all moving close to the speed of light and surviving just 40 billionths of a second, the results prove that antiatoms can exist. Researchers are now trying to trap and probe them.
Antimatter is identical to ordinary matter except that the electrical charges are reversed.
An electron is negative, whereas an antielectron, or positron, is positive. Only now, however, have they managed to combine the two types of particles to create an antiatom. They directed a beam of antiprotons, moving near the speed of light, through a jet of xenon atoms. Most of the antiprotons passed through the jet, but on occasion one interacted with a xenon atom. The energy of the interaction gave birth to pairs of electrons and positrons.