High-resolution Laboratory Measurements of K-shell X-ray Line Polarization and Excitation Cross Sections in Heliumlike S XV Ions
arXiv:2106.06493 · doi:10.3847/1538-4357/abf1ea
Abstract
We report measurements of electron-impact excitation cross sections for the strong K-shell n=2-1 transitions in S XV using the LLNL EBIT-I electron beam ion trap, two crystal spectrometers, and the EBIT Calorimeter Spectrometer. The cross sections are determined by direct normalization to the well known cross sections of radiative electron capture, measured simultaneously. Using contemporaneous polarization measurements with the two crystal spectrometers, whose dispersion planes are oriented parallel and perpendicular to the electron beam direction, the polarization of the direct excitation line emission is determined, and in turn the isotropic total cross sections are extracted. We further experimentally investigate various line-formation mechanisms, finding that radiative cascades and collisional inner-shell ionization dominate the degree of linear polarization and total line-emission cross sections of the forbidden line .
arXiv comment16 Pages, 9 Figures, published in ApJ
References in corpus (30)
- Updated Atomic Data and Calculations for X-ray Spectroscopy
- X-ray Imaging Spectroscopy of Abell 1835
- The Quiescent Intracluster Medium in the Core of the Perseus Cluster
- CHIANTI - An atomic database for Emission Lines. Version 8
- X-ray photoionized plasma diagnostics with Helium-like ions. Application to Warm Absorber-Emitter in Active Galactic Nuclei
- XMM-Newton observations of the cluster of galaxies Sersic 159-03
- High resolution X-Ray spectroscopy of Zeta Puppis with the XMM-Newton Reflection Grating Spectrometer
- A Fast Algorithm for Cosmic Rays Removal from Single Images
- He-like ions as practical astrophysical plasma diagnostics: From stellar coronae to active galactic nuclei
- Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi
- The Athena X-ray Integral Field Unit (X-IFU)
- XIPE: the X-ray Imaging Polarimetry Explorer
- Solar abundance ratios of the iron-peak elements in the Perseus Cluster
- XMM-Newton observations of the cluster of galaxies Abell496 -Measurements of the elemental abundances in the intracluster medium-
- Fe XXV and Fe XXVI lines from low velocity, photoionised gas in the X-ray spectra of AGN
- Measurements and analysis of helium-like triplet ratios in the X-ray spectra of O-type stars
- Scientific Prospects for Hard X-ray Polarimetry
- Measurements of resonant scattering in the Perseus cluster core with Hitomi SXS
- Polarization measurement of dielectronic recombination transitions in highly charged krypton ions
- Polarization signatures of strong gravity in AGN accretion discs
- Are stellar coronae optically thin in X-rays? - A systematic investigation of opacity effects
- EBIT Charge-Exchange Measurements and Astrophysical Applications
- High-Resolution X-Ray Spectroscopy of the Galactic Supernova Remnant Puppis A with the XMM-Newton RGS
- Polarization of K-shell dielectronic recombination satellite lines of Fe XIX-XXV and its application for diagnostics of anisotropies of hot plasmas
- Laboratory Measurements of the K-shell transition energies in L-shell ions of Si and S
- Strong higher-order resonant contributions to x-ray line polarization in hot plasmas
- Revisiting the Fe XVII line emission problem: laboratory measurements of the 3s-2p and 3d-2p line-formation channels
- Angular correlations in the two--photon decay of helium--like heavy ions
- Plasma Diagnostics of the Supernova Remnant N132D Using Deep XMM-Newton Observations with the Reflection Grating Spectrometer
- Anisotropic X-ray emission in AGN accretion discs