0000000000315660
AUTHOR
David F. Phillips
Special Relativity and the Single Antiproton: Fortyfold Improved Comparison ofp¯andpCharge-to-Mass Ratios
The measured ratio of charge-to-mass ratios for the antiproton and proton is $1.0000000015\ifmmode\pm\else\textpm\fi{}0.0000000011$. This $1$ part in ${10}^{9}$ comparison ( $1$ ppb) is possible because a single $\overline{p}$ or $p$ is now directly observed while trapped in an open access Penning trap. The comparison is the most accurate mass spectrometry of particles with opposite charge, and is the most sensitive test of $\mathrm{CPT}$ invariance for a baryon system. It is 40 times more accurate than our earlier comparison with many trapped antiprotons and protons, and is more than 45 000 times more accurate than earlier comparisons made with other techniques.
Improved comparison of bar P and P charge-to-mass ratios
The measured ratio of charge-to-mass ratios for the antiproton and proton is 1.000 000 001 5 ± 0.000 000 001 1. This 1 part in 109 comparison (1 ppb) is possible because a single or p is now directly observed while trapped in an open access Penning trap. The comparison is the most accurate mass spectrometry of particles with opposite charge and is the most sensitive test of CPT invariance for a baryon system. It is 40 times more accurate than our earlier comparison with many trapped antiprotons and protons, and is more than 45 000 times more accurate than earlier comparisons made with other techniques.