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

There are major discrepancies between recent B-spline R-matrix (BSR) andDirac Atomic R-matrix Code (DARC) calculations regarding electron-impactexcitation rates for transitions in Mg$^{4+}$, with claims that the DARCcalculations are much more accurate. To identify possible reasons for thesediscrepancies and to estimate the accuracy of the various results, we carriedout independent BSR calculations with the same 86 target states as in theprevious calculations, but with a different and more accurate representation ofthe target structure. We find close agreement with the previous BSR results forthe majority of transitions, thereby confirming their accuracy. At the sametime the differences with the DARC results are much more pronounced. Thediscrepancies in the final results for the collision strengths are mainly dueto differences in the structure description, specifically the inclusion ofcorrelation effects, and due to the likely occurrence of pseudoresonances. Tofurther check the convergence of the predicted collision rates, we carried outeven more extensive calculations involving 316 states of Mg$^{4+}$. Extendingthe close-coupling expansion results in major corrections for transitionsinvolving the higher-lying states and allows us to assess the likelyuncertainties in the existing datasets.

Benchmark calculations for electron-impact excitation of Mg$^{4+}$