One-loop self-energy correction to the 1s and 2s hyperfine splitting in H-like systems -: art. no. 012506

The one-loop self-energy correction to the hyperfine splitting of the 1s and 2s levels in H-like low-Z atoms is evaluated to all orders in Z alpha. The results are compared to perturbative calculations. The residual higher-order contribution is evaluated. Implications to the specific difference of the hyperfine-structure intervals 8 Delta nu (2)-Delta nu (1) in He+ are investigated.