antihydrogen

physics

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June 18, 2026

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Antihydrogen is the antimatter counterpart of hydrogen. Antimatter is composed of subatomic particles with opposite electric charges and magnetic moments compared to ordinary matter. For instance, antihydrogen consists of a positron (positive charge) orbiting an antiproton (negative charge).12

When matter and antimatter come into contact, they annihilate each other, releasing significant energy. While positrons and antiprotons have been created and studied, large amounts of antimatter have not been observed in the universe, posing a puzzle for cosmology and particle physics known as matter-antimatter asymmetry.2

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antimatter
…an ordinary atom—in this case, antihydrogen, the simplest antiatom, consisting of a positron in orbit around an antiproton nucleus. They did so by firing antiprotons through a xenon-gas jet. In the strong electric fields surrounding the xenon nuclei, some antiprotons created pairs of electrons and positrons; a few of the…
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…an ordinary atom—in this case, antihydrogen, the simplest antiatom, consisting of a positron in orbit around an antiproton nucleus. They did so by firing antiprotons through a xenon-gas jet. In the strong electric fields surrounding the xenon nuclei, some antiprotons created pairs of electrons and positrons; a few of the…
Read More