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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Context: Chemically peculiar A type (Ap) stars are a subgroup of the CP2stars which exhibit anomalous overabundances of numerous elements, e.g. Fe, Cr,Sr and rare earth elements. The pulsating subgroup of the Ap stars, the roApstars, present ideal laboratories to observe and model pulsational signaturesas well as the interplay of the pulsations with strong magnetic fields andvertical abundance gradients. Aims: Based on high resolution spectroscopicobservations and observed stellar energy distributions we construct a selfconsistent model atmosphere, that accounts for modulations of thetemperature-pressure structure caused by vertical abundance gradients, for theroAp star 10 Aquilae (HD 176232). We demonstrate that such an analysis can beused to determine precisely the fundamental atmospheric parameters required forpulsation modelling. Methods: Average abundances were derived for 56 species.For Mg, Si, Ca, Cr, Fe, Co, Sr, Pr, and Nd vertical stratification profileswere empirically derived using the ddafit minimization routine together withthe magnetic spectrum synthesis code synthmag. Model atmospheres were computedwith the LLModels code which accounts for the individual abundances andstratification of chemical elements. Results: For the final model atmosphereTeff=7550 K and log g=3.8 were adopted. While Mg, Si, Co and Cr exhibit steepabundance gradients Ca, Fe and Sr showed much wider abundance gradients betweenlog tau_5000=-1.5 and 0.5. Elements Mg and Co were found to be the leaststratified, while Ca and Sr showed strong depth variations in abundance of upto ~ 6 dex.

A self consistent chemically stratified atmosphere model for the roAp star 10 Aquilae