Webber, KB;
Hansen, TT;
Marshall, JL;
Simon, JD;
Pace, AB;
Mutlu-Pakdil, B;
Drlica-Wagner, A;
... Yanny, B; + view all
(2023)
Chemical Analysis of the Brightest Star of the Cetus II Ultrafaint Dwarf Galaxy Candidate.
The Astrophysical Journal
, 959
(2)
, Article 141. 10.3847/1538-4357/ad0385.
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Abstract
We present a detailed chemical abundance analysis of the brightest star in the ultrafaint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra. For this star, DES J011740.53-173053, abundances or upper limits of 18 elements from carbon to europium are derived. Its chemical abundances generally follow those of other UFD galaxy stars, with a slight enhancement of the α-elements (Mg, Si, and Ca) and low neutron-capture element (Sr, Ba, and Eu) abundances supporting the classification of Cetus II as a likely UFD. The star exhibits lower Sc, Ti, and V abundances than Milky Way (MW) halo stars with similar metallicity. This signature is consistent with yields from a supernova originating from a star with a mass of ∼11.2 M ⊙. In addition, the star has a potassium abundance of [K/Fe] = 0.81, which is somewhat higher than the K abundances of MW halo stars with similar metallicity, a signature that is also present in a number of UFD galaxies. A comparison including globular clusters and stellar stream stars suggests that high K is a specific characteristic of some UFD galaxy stars and can thus be used to help classify objects as UFD galaxies.
| Type: | Article |
|---|---|
| Title: | Chemical Analysis of the Brightest Star of the Cetus II Ultrafaint Dwarf Galaxy Candidate |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.3847/1538-4357/ad0385 |
| Publisher version: | http://dx.doi.org/10.3847/1538-4357/ad0385 |
| Language: | English |
| Additional information: | © 2024 IOP Publishing. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence (http://creativecommons.org/licenses/by/4.0/). |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy |
| URI: | https://discovery-pp.ucl.ac.uk/id/eprint/10185185 |
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