Hyperfine structure of the S levels of the muonic helium ion

Abstract

Corrections of the α5 and α6 orders to the energy spectrum of the hyperfine splitting of the 1S and 2S levels of the muonic helium ion are calculated with the inclusion of the electron vacuum polarization effects, nuclear-structure corrections, and recoil effects. The values ΔE hfs(1S) = −1334.56 meV and ΔE hfs(2S) = −166.62 meV obtained for hyperfine splitting values can be considered as reliable estimates for comparison with experimental data. The hyperfine structure interval Δ12 = 8ΔE hfs(2S) − ΔE hfs(1S) = 1.64 meV can be used to verify QED predictions.