A new benchmark of soft X-ray transition energies of Ne, CO, and SF: paving a pathway towards ppm accuracy
arXiv:2203.03725 · doi:10.1140/epjd/s10053-022-00355-0
Abstract
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 features of Ne, CO, and SF gases, by measuring their photo ion-yield spectra at the BESSY II synchrotron facility simultaneously with the 1s-np fluorescence emission of He-like ions produced in the Polar-X EBIT. Accurate ab initio calculations of transitions in these ions provide the basis of the calibration. While the CO result agrees well with previous measurements, the SF spectrum appears shifted by ~0.5 eV, about twice the uncertainty of the earlier results. Our result for Ne shows a large departure from earlier results, but may suffer from larger systematic effects than our other measurements. The molecular spectra agree well with our results of time-dependent density functional theory. We find that the statistical uncertainty allows calibrations in the desired range of 1-10 meV, however, systematic contributions still limit the uncertainty to ~40-100 meV, mainly due to the temporal stability of the monochromator energy scale. Combining our absolute calibration technique with a relative energy calibration technique such as photoelectron energy spectroscopy will be necessary to realize its full potential of achieving uncertainties as low as 1-10 meV.
13 pages, 7 figures
References in corpus (9)
- A fast and long-lived outflow from the supermassive black hole in NGC 5548
- The Heidelberg compact electron beam ion traps
- SNR 1E 0102.2-7219 as an X-ray Calibration Standard in the 0.5-1.0 keV Bandpass and Its Application to the CCD Instruments aboard Chandra, Suzaku, Swift and XMM-Newton
- Calibration and in orbit performance of the reflection grating spectrometer onboard XMM-Newton
- Chandra/HETGS Observations of the Capella System: the Primary as a Dominating X-ray Source
- High-Precision Determination of Oxygen-K Transition Energy Excludes Incongruent Motion of Interstellar Oxygen
- Detection capabilities of the Athena X-IFU for the warm-hot intergalactic medium using gamma-ray burst X-ray afterglows
- Vibrational effects in x-ray absorption (XAS) and resonant inelastic x-ray scattering (RIXS) using a semiclassical scheme
- Condensed Matter Astrophysics: A Prescription for Determining the Species-Specific Composition and Quantity of Interstellar Dust using X-rays