Radiative Corrections to the Muonium Hyperfine Structure. II. The $\alpha (Z\alpha {)}^2$ Correction

M. Nio, T. Kinoshita

This is the second of a series of papers on the radiative corrections of order ${\alpha }^2(Z\alpha )$, $\alpha (Z\alpha {)}^2$, and various logarithmic terms of order ${\alpha }^4$, to the hyperfine structure of th…