Antihydrogen ground-state hyperfine splitting at the ppm level · revision history
Revision 2
Accepted · core change · record
Changes against revision 1:
- Title
- Antihydrogen ground-state hyperfine splitting at the ppm level
- Plain
- The tiny splitting caused by the magnetic interaction of the antiproton and positron is sensitive to different possible symmetry violations than the optical line. It has been measured only to a few parts in 10000.
- Precise · changed · core
- Revision 1: Measure the zero-field ground-state hyperfine splitting of antihydrogen (hydrogen: 1420.405751768 MHz) with relative uncertainty below 1e-6, using either an in-beam Rabi method (ASACUSA) or trapped-atom microwave spectroscopy (ALPHA), and determine whether it differs from hydrogen.
- Revision 2: Measure the zero-field ground-state hyperfine splitting of antihydrogen (hydrogen: 1420.405751768 MHz) with relative uncertainty below $10^{-6}$, using either an in-beam Rabi method (ASACUSA) or trapped-atom microwave spectroscopy (ALPHA), and determine whether it differs from hydrogen.
- Settled by
- A beam or trap measurement of the Hbar hyperfine splitting with ppm uncertainty compared to the hydrogen maser value.
- Kind
- well-posed
- Answer type
- yes-no
- References
- (empty)
- Literature status
- open
- Status note
- (empty)
- Posed since
- (empty)
Decisions
- Accept · 2026-10-15 · record