New method of precise measurement of positronium hyperfine splitting

A. Ishida, G. Akimoto, Y. Sasaki +8

The ground state hyperfine splitting of positronium, ${\Delta }_{\mathrm{HFS}}$, is sensitive to high order corrections of QED. A new calculation up to $\mathrm{O}({\alpha }^3\ln \alpha )$ has revealed…