In a paper published today in Nature, the BASE collaboration at CERN reports the most precise measurement ever made of the magnetic moment of the antiproton, allowing a fundamental comparison between matter and antimatter.
The BASE measurement shows that the magnetic moments of the proton and antiproton are identical, apart from their opposite signs, within the experimental uncertainty of 1.5 parts per billion. The result outperforms their latest record, which was presented earlier this year, by a factor of 350. It is the first time physicists have carried out a measurement with higher precision on the antiproton than on the proton.
BASE at LUH: "Quantum Logic Spectroscopy of (Anti-)Protons"