A Single Positron Was Reportedly Confined and Controlled for Months
PhysicsUnverifiedUpdated:
A Northwestern University team reportedly kept a single positron—an electron’s antimatter counterpart—isolated in a cryogenic Penning trap for months while controlling its quantum motion.
Controlling one positron in a cryogenic vacuum
According to ScienceAlert, physicists at Northwestern University slowed positrons from a radioactive sodium source, guided a small fraction into a Penning trap, and held one positron in a cryogenic vacuum for months. The report says they cooled its cyclotron motion to its lowest quantum state, used microwaves to move it between energy levels, and detected those changes and spin flips without disturbing the measured states.
The report describes the difficulty of slowing positrons and isolating them from electrons, but it does not provide a directly comparable earlier confinement duration or control result.
The team reportedly captured one positron, kept it isolated for months, and controlled and detected discrete changes in its motion and spin within the trap.
Magnetic-moment comparison results remain ahead
The reported control of a single positron could enable a high-precision measurement of its magnetic moment for comparison with the electron’s. The researchers are still obtaining that measurement, so no CPT-symmetry comparison result has been reported.
Sources
- ScienceAlertPhysicists Trapped a Particle of Antimatter And Kept It Caged For MonthsRead source →