One of the most enduring and intensively studied problems of x-ray astronomy is the
disagreement of state-of-the art theory and observations for the intensity ratio of two Fe XVII …

The problem of missing baryons in the local universe remains an open question. One
proposed alternative is that at low redshifts missing baryons are in the form of the warm-hot …

By exciting a series of 1 s 2 S 0 1→ 1 snp P 1 1 transitions in heliumlike nitrogen ions with
linearly polarized monochromatic soft x rays at the Elettra facility, we found a change in the …

We describe the atomic database of the xstar spectral modeling code, summarizing the
systematic upgrades carried out in the past twenty years to enable the modeling of K-lines …

Metastable states of ions can be sufficiently populated in absorbing and emitting
astrophysical media, enabling spectroscopic plasma-density diagnostics. Long-lived states …

The transition energies of the two 1 s core-excited soft x-ray lines (dubbed q and r) from 1 s 2
2 s 1 S 1/2 to the respective upper levels 1 s (2 S) 2 s 2 p (3 P) 2 P 3/2 and 2 P 1/2 of Li-like …

A key requirement for the correct interpretation of high-resolution X-ray spectra is that
transition energies are known with high accuracy and precision. We investigate the K-shell …

In this work, we present an experiment conducted at the S-EBIT-I ion trap of GSI. It involved
the study of ion-electron collisions of Fe and Ba ions in various charge states with the …

High-resolution K-shell photoionization cross-sections for the C-like atomic nitrogen ion (N+)
are reported in the 398 eV (31.15 Å) to 450 eV (27.55 Å) energy (wavelength) range. The …

We improve eight-fold the energy accuracy of the strongest soft X-ray transitions of Fe XVII
ions by resonantly exciting them in an electron beam ion trap with a monochromatic beam at …