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

As part of a multifaceted effort to exploit better the asteroseismologicalpotential of the pulsating sdB star Feige 48, we present an improvedspectroscopic analysis of that star based on new grids of NLTE, fullyline-blanketed model atmospheres. To that end, we gathered four high S/Ntime-averaged optical spectra of varying spectral resolution from 1.0 \AA\ to8.7 \AA, and we made use of the results of four independent studies to fix theabundances of the most important metals in the atmosphere of Feige 48. The meanatmospheric parameters we obtained from our four spectra of Feige 48 are :Teff= 29,850 $\pm$ 60 K, log $g$ = 5.46 $\pm$ 0.01, and log N(He)/N(H) =$-$2.88 $\pm$ 0.02. We also modeled for the first time the He II line at 1640\AA\ from the STIS archive spectrum of the star and we found with this line aneffective temperature and a surface gravity that match well the values obtainedwith the optical data. With some fine tuning of the abundances of the metalsvisible in the optical domain we were able to achieve a very good agreementbetween our best available spectrum and our best-fitting synthetic one. Ourderived atmospheric parameters for Feige 48 are in rather good agreement withprevious estimates based on less sophisticated models. This underlines therelatively small effects of the NLTE approach combined with line blanketing inthe atmosphere of this particular star, implying that the current estimates ofthe atmospheric parameters of Feige 48 are reliable and secure.

Improved determination of the atmospheric parameters of the pulsating sdB star Feige 48