Angle-resolved x-ray spectroscopic scheme to determine overlapping hyperfine splittings in highly charged helium-like ions

TL;DR

This paper proposes an angle-resolved x-ray spectroscopy method to measure hyperfine splittings in highly charged helium-like ions, enabling high-precision resolution of overlapping hyperfine resonances using current detectors.

Contribution

It introduces a novel spectroscopic scheme that utilizes angular and polarization measurements to resolve overlapping hyperfine structures in highly charged ions.

Findings

The scheme can measure hyperfine splittings with a relative accuracy of about 10^{-4}.

Angular and polarization characteristics depend strongly on hyperfine resonance splitting.

The method is feasible with existing photon detection technology.

Abstract

An angle-resolved x-ray spectroscopic scheme is presented for determining the hyperfine splitting of highly charged ions. For helium-like ions, in particular, we propose to measure either the angular distribution or polarization of the $1s2p~^{3}P_{1}, F \rightarrow 1s^{2}~^{1}S_{0}, F_{f}$ emission following the stimulated decay of the initial $1s2s~^{1}S_{0}, F_{i}$ level. It is found that both the angular and polarization characteristics of the emitted x-ray photons strongly depends on the (relative) \textit{splitting} of the partially overlapping hyperfine $1s2p~^{3}P_{1}, F$ resonances and may thus help resolve their hyperfine structure. The proposed scheme is feasible with present-day photon detectors and allows a measurement of the hyperfine splitting of helium-like ions with a relative accuracy of about $10^{-4}$.