EUV magnetic-dipole lines from highly-charged high-Z ions with an open 3d shell

TL;DR

This study used an electron beam ion trap to produce and analyze highly-charged high-Z ions with open 3d shells, identifying 133 new EUV spectral lines mainly from magnetic-dipole transitions within ground states.

Contribution

It reports the first identification of 133 new EUV spectral lines from highly-charged high-Z ions with open 3d shells, expanding atomic data for these ions.

Findings

Identified 133 new spectral lines in the EUV range.

Most lines originate from magnetic-dipole transitions within ground states.

Spectral lines were assigned through detailed collisional-radiative modeling.

Abstract

The electron beam ion trap (EBIT) at the National Institute of Standards and Technology was used to produce highly-charged ions of hafnium, tantalum and gold with an open 3d shell. The extreme-ultraviolet (EUV) spectra from these ions were recorded with a flat-field grazing-incidence spectrometer in the wavelength range of 4.5 nm to 25 nm. A total of 133 new spectral lines, primarily due to magnetic-dipole transitions within the ground-state $3d^n$ configurations of the Co-like to K-like ions, were identified by comparing energy-dependent experimental spectra with a detailed collisional-radiative modeling of the EBIT plasma.