Accessing the hyperfine splitting in highly charged helium-like ions via angle-resolved x-ray spectroscopic analysis

A new scheme is presented for determining the hyperfine splitting of highly charged ions via angle-resolved spectroscopic analysis. In particular, we propose two measurements on the angular distribution and linear polarization of the emission line 1 s 2 p ³ P ₁, F = I − 1, I , I + 1 → 1 s ^{2 1} S ₀, F_f = I of He-like isotopic ions, following the stimulated decay of the 1 s 2 s ¹ S ₀, F_i = I level. We find that the angular and polarization behavior of the emitted photons strongly depends on the splitting of the overlapping hyperfine 1 s 2 p ³ P ₁, F resonances, which could be a promising "signature" for the hyperfine splitting determination. (paper)