English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We report measurements of electron-impact excitation cross sections for thestrong K-shell n=2-1 transitions in S XV using the LLNL EBIT-I electron beamion trap, two crystal spectrometers, and the EBIT Calorimeter Spectrometer. Thecross sections are determined by direct normalization to the well known crosssections of radiative electron capture, measured simultaneously. Usingcontemporaneous polarization measurements with the two crystal spectrometers,whose dispersion planes are oriented parallel and perpendicular to the electronbeam direction, the polarization of the direct excitation line emission isdetermined, and in turn the isotropic total cross sections are extracted. Wefurther experimentally investigate various line-formation mechanisms, findingthat radiative cascades and collisional inner-shell ionization dominate thedegree of linear polarization and total line-emission cross sections of theforbidden line $z$.

High-resolution Laboratory Measurements of K-shell X-ray Line Polarization and Excitation Cross Sections in Heliumlike S XV Ions