A high-precision abundance analysis of the nuclear benchmark star HD 20
Journal
Date Issued
2020
Author(s)
Michael Hanke
•
Camilla Juul Hansen
•
Hans-Günter Ludwig
•
•
Andrew McWilliam
•
Eva K. Grebel
•
Luciano Piersanti
Abstract
We present our chemical abundance investigation of the metal-poor
([Fe/H]=-1.60 dex), r-process-enriched ([Eu/Fe]=0.73 dex) halo star HD 20 using
novel and archival high-resolution spectra at outstanding signal-to-noise
ratios. By combining one of the first asteroseismic gravity measurements in the
metal-poor regime from a TESS light curve with non-LTE analyses of iron lines,
we derive a set of highly accurate and precise stellar parameters. These allow
us to delineate a chemical pattern comprised of solid detections of 48
elements, including 28 neutron-capture elements, which establishes HD 20 among
the few benchmark stars that have almost complete patterns with low systematic
dependencies on the stellar parameters. Our light-element (Z<30) abundances are
representative of other, similarly metal-poor stars in the Galactic halo with
contributions from core-collapse supernovae of type II. A comparison to the
scaled solar r-pattern shows that the lighter neutron-capture elements
(37
Volume
635
Start page
A104
Issn Identifier
0004-6361
Ads BibCode
2020A&A...635A.104H
Rights
open.access
File(s)![Thumbnail Image]()
Loading...
Name
Hanke_2020_A&A_635_104.pdf
Description
Pdf editoriale
Size
6.93 MB
Format
Adobe PDF
Checksum (MD5)
1a136f7ebbecb489bb86285ce173c626
