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 Tools annual

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 monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We present a homogeneous set of accurate atmospheric parameters for a sampleof eleven very metal-poor (-3.32 <= [Fe/H] <= -2.61) stars in the Sextans dwarfspheroidal galaxy (dSph) and the non-local thermodynamic equilibrium (NLTE)abundances of, at least, seven chemical elements based on high-resolutionUVES/VLT and HDS/Subaru spectra. For each star, its effective temperature andsurface gravity were derived from the spectral energy distribution and theknown distance, and the Fe abundance was obtained as the average from lines ofFe I and Fe II. Based on abundances of Mg, Ca, and Ti, we show that all theinvestigated stars reveal alpha-enhancements of 0.4~dex to 0.2~dex, and thereis a hint of a decline in alpha/Fe for [Fe/H] > -2.8. The Sextans stars aredeficient in Ba. The new result is an extremely tight relation between Ba andMg, suggesting their common origin in massive stars and Ba synthesis in ther-process events on the timescales of standard supernovae. The exception is aC-enhanced star S 15-19 which is strongly enhanced in Ba. This star is unlikelyto be a CEMP-s star because of low abundances of Sr and Y ([Y/Fe] < -1) thatare produced in the s-process as efficiently as Ba and a non-detection ofvariation in the radial velocity. No distinctions from the Milky Way halo andthe Sculptor and Ursa Minor dSphs were found in a history of early enrichmentin Na and Ni, namely, the Sextans stars are deficient in Na and haveclose-to-solar Ni/Fe.

The formation of the Milky Way halo and its dwarf satellites: A NLTE-1D abundance analysis. V. The Sextans galaxy