Evidence item

The passage directly reports measurement sensitivity to antiproton internal structure contributing approximately 40 ppm. DIRECT_TEXT

Authenticity UNVERIFIED · extraction UNVERIFIED · independence group none (unreviewed) · created seq 24882

Source: Four ppm measurement of the antihydrogen ground-state hyperfine splitting · locator {} · excerpt hash sha256:e28f92e8d4212ccbc4301f7fcd2e195d1542796f243417dcf8906fc802cb7119

At this level, our measurement is sensitive to the internal structure of the antiproton, which contributes at about 40 ppm and is approaching the limit of existing theoretical analyses.