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

Young open clusters (t<200 Myr) have been observed to exhibit severalpeculiarities in their chemical compositions, from a slightly sub-solar ironcontent, super-solar abundances of some atomic species (e.g. ionised chromium),and atypical enhancements of [Ba/Fe], with values up to +0.7 dex. Regarding thebehaviour of the other $s$-process elements like yttrium, zirconium, lanthanum,and cerium, there is general disagreement in the literature. In this work weexpand upon our previous analysis of a sample of five young open clusters(IC2391, IC2602, IC4665, NGC2516, and NGC2547) and one star-forming region(NGC2264), with the aim of determining abundances of different neutron-captureelements, mainly CuI, SrI, SrII, YII, ZrII, BaII, LaII, and CeII. We analysedhigh-resolution, high signal-to-noise spectra of 23 solar-type stars observedwithin the \textit{Gaia}-ESO survey. We find that our clusters have solar[Cu/Fe] within the uncertainties, while we confirm the super-solar [Ba/Fe]values (from +0.22 to +0.64 dex). Our analysis also points to mildly enhanced[Y/Fe] values (from 0 and +0.3 dex). For the other $s$-process elements we findthat [X/Fe] ratios are solar at all ages. It is not possible to reconcile theanomalous behaviour of Ba and Y at young ages with standard stellar yields andGalactic chemical evolution model predictions. Thus, we explore differentpossible scenarios related to the behaviour of spectral lines, from thesensitivity to the presence of magnetic fields to the first ionisationpotential effect. We also investigate the possibility that they may arise fromalterations of the structure of the stellar photosphere due to higher levels ofactivity in such young stars. We are still unable to explain theseenhancements, but we suggest that other elements (i.e. La) might be morereliable tracer of the $s$-process at young ages and encourage furtherobservations.

astronomy and astrophysics

The Gaia-ESO Survey: A new approach to chemically characterising young  open clusters II. Abundances of the neutron-capture elements Cu, Sr, Y, Zr,  Ba, La, and Ce