Hyperfine structure of the excited state 1s1/2(e)2s1/2(μ) of the muonic helium atom

摘要

The recoil, vacuum polarization, and electron vertex corrections of first and second orders in the fine structure constant α and the ratio of electron to muon and electron to α-particle masses are calculated for the hyperfine splitting of the 1s1/2(e)2s1/2(μ) state of muonic helium atom (μe24He) on the basis of perturbation theory. We obtain a total result for the muonically excited state hyperfine splitting Δνhfs=4295.66 MHz, which improves previous calculations, taking additional corrections into account, and a more accurate treatment of the electron vertex contribution.