High-Precision Transition Energy Measurements of Neon-like Fe XVII Ions

Abstract

We improve by a factor of 4-20 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 the P04 beamline of the PETRA III synchrotron facility. By simultaneously tracking instantaneous photon-energy fluctuations with a high-resolution photoelectron spectrometer, we minimize systematic uncertainties down to 10-15 meV, or velocity equivalent $\pm \sim$5 km s${}^{-1}$ in their rest energies, substantially improving our knowledge of this key astrophysical ion. Our large-scale configuration-interaction computations include more than four million relativistic configurations and agree with the experiment at a level without precedent for a 10-electron system. Thereby, theoretical uncertainties for interelectronic correlations become far smaller than those of quantum electrodynamics (QED) corrections. The present QED benchmark strengthens our trust in future calculations of many other complex atomic ions of interest to astrophysics, plasma physics, and for the development of optical clocks with highly charged ions.

14 pages, 2 figures, 4 tables, published version

References in corpus (22)

• CHIANTI -- an atomic database for emission lines -- Paper XVI: Version 10, further extensions
• On the use of C-stat in testing models for X-ray spectra
• An Optical Atomic Clock Based on a Highly Charged Ion
• The Athena X-ray Integral Field Unit (X-IFU)
• The Heidelberg compact electron beam ion traps
• QED shifts in multivalent heavy ions
• Fe XVII X-ray Line Ratios for Accurate Astrophysical Plasma Diagnostics
• Extended relativistic configuration interaction and many-body perturbation calculations of spectroscopic data for the $n\le 6$ configurationsin ne-like ions between Cr XV and Kr XXVII
• X-ray spectra of the Fe-L complex
• High Resolution Photoexcitation Measurements Exacerbate the Long-Standing Fe XVII Oscillator Strength Problem
• Theoretical energy levels of $1sns$ and $1snp$ states of helium-like ions
• New Measurement Resolves Key Astrophysical Fe XVII Oscillator Strength Problem
• Astrophysical line diagnosis requires non-linear dynamical atomic modeling
• Chandra/HETGS Observations of the Capella System: the Primary as a Dominating X-ray Source
• X-ray spectra of the Fe-L complex II: atomic data constraints from EBIT experiment and X-ray grating observations of Capella
• High-Precision Determination of Oxygen-K$\alpha$ Transition Energy Excludes Incongruent Motion of Interstellar Oxygen
• Observation of strong two-electron--one-photon transitions in few-electron ion
• Comprehensive Laboratory Measurements Resolving the LMM Dielectronic Recombination Satellite Lines in Ne-like Fe XVII Ions
• X-ray spectra of the Fe-L complex III: systematic uncertainties in the atomic data
• A new benchmark of soft X-ray transition energies of Ne, CO${}_2$, and SF${}_6$: paving a pathway towards ppm accuracy
• A detailed analysis of X-ray emission line velocities of Capella from over 20 years of Chandra/HETG spectroscopy
• Multiple photodetachment of silicon anions via K-shell excitation and ionization

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