Antiproton magnetic moment determined from the HFS of antiprotonic helium

TL;DR

This study precisely measures the antiproton magnetic moment using hyperfine structure of antiprotonic helium, providing a new value that closely aligns with the proton's magnetic moment and improves measurement accuracy.

Contribution

It presents the first independent measurement of the antiproton magnetic moment through hyperfine structure analysis, with a tenfold increase in precision over previous results.

Findings

Antiproton magnetic moment determined as -2.7862 (83) nuclear magnetons.

Measurement precision improved by a factor of 10.

Result agrees with proton magnetic moment within 2.9 x 10^-3.

Abstract

We report a determination of the antiproton magnetic moment, measured in a three-body system, independent of previous experiments. We present results from a systematic study of the hyperfine (HF) structure of antiprotonic helium where we have achieved a precision more than a factor of 10 better than our first measurement. A comparison between the experimental results and three-body quantum electrodynamic (QED) calculations leads to a new value for the antiproton magnetic moment is -2.7862 (83) nuclear magnetons, which agrees with the magnetic moment of the proton within 2.9 x 10e-3.