State-resolved valence shell photoionization of Be-like ions: experiment and theory

TL;DR

This study combines high-resolution experiments and theoretical calculations to analyze the state-resolved valence shell photoionization of Be-like ions, providing detailed insights into metastable state contributions with high precision.

Contribution

The paper presents the first high-resolution experimental measurements of state-resolved photoionization of Be-like ions and compares them with advanced theoretical calculations.

Findings

Resolved contributions from individual metastable states.

Achieved calibration uncertainties of 1 to 10 meV.

Revealed good agreement between experiment and theory.

Abstract

High-resolution photoionization experiments were carried out using beams of Be-like C$^{2+}$, N$^{3+}$, and O$^{4+}$ ions with roughly equal populations of the $^1$S ground-state and the $^3$P$^o$ manifold of metastable components. The energy scales of the experiments are calibrated with uncertainties of 1 to 10 meV depending on photon energy. Resolving powers beyond 20,000 were reached allowing for the separation of contributions from the individual metastable $^3$P$^o_0$, $^3$P$^o_1$, and $^3$P$^o_2$ states. The measured data compare favourably with semi-relativistic Breit-Pauli R-matrix