Scientists Trap Single Antimatter Particle for Months

Northwestern University physicists have achieved unprecedented quantum control over a single positron, capturing the antimatter particle from sodium-22 radioactive decay and suspending it in a near-perfect vacuum for months on November 12, 2026. This breakthrough establishes a one-positron quantum cyclotron, cooling the energetic particle to approximately 300 millikelvins, which is 0.3 degrees Celsius above absolute zero, allowing researchers to observe and manipulate individual quantum energy states. The study leader Gerald Gabrielse and his research team aim to use this precise confinement to compare the magnetic properties of positrons and electrons with extreme accuracy. By testing whether their magnetic moments are equal in magnitude, the team hopes to uncover potential flaws in the Standard Model of particle physics and investigate why the universe contains overwhelmingly more matter than antimatter. The experiment overcomes the fundamental challenge of matter-antimatter annihilation by utilizing specialized electric and magnetic fields to keep the positron isolated from physical container walls. This isolation prevents destructive contact with ordinary matter, enabling long-term observation and measurement of fundamental particle characteristics that could resolve one of physics' greatest mysteries. This milestone bridges decades of research on electron magnetic moments and low-energy antiprotons, opening new experimental pathways for testing fundamental physical symmetries. Researchers plan to leverage these ultra-precise magnetic measurements to search for unambiguous evidence of physics beyond the Standard Model.