dc.contributor.author |
Shejeelammal, J |
|
dc.contributor.author |
Goswami, A |
|
dc.date.accessioned |
2022-09-02T05:22:57Z |
|
dc.date.available |
2022-09-02T05:22:57Z |
|
dc.date.issued |
2022-08-01 |
|
dc.identifier.citation |
The Astrophysical Journal, Vol. 934, No. 2, 110 |
en_US |
dc.identifier.issn |
1538-4357 |
|
dc.identifier.uri |
http://hdl.handle.net/2248/8036 |
|
dc.description |
Open Access |
en_US |
dc.description.abstract |
Elemental abundances of extrinsic carbon stars provide insight into the poorly understood origin and evolution of
elements in the early Galaxy. In this work, we present the results of a detailed spectroscopic analysis of four
potential carbon star candidates from the Hamburg/ESO Survey (HES): HE 0457−1805, HE 0920−0506,
HE 1241−0337, and HE 1327−2116. This analysis is based on the high-resolution spectra obtained with
Mercator/HERMES (R ∼ 86,000) and SUBARU/HDS (R ∼ 50,000). Although the abundances of a few elements,
such as Fe, C, and O, are available from medium-resolution spectra, we present the first ever detailed high resolution spectroscopic analysis for these objects. The objects HE 0457−1805 and HE 1241−0337 are found to
be CEMP-s stars, HE 0920−0506 a CH star, and HE 1327−2116 a CEMP-r/s star. The object HE 0457−1805 is a
confirmed binary, whereas the binary status of the other objects is unknown. The locations of program stars on the
diagram of absolute carbon abundance A(C) versus [Fe/H] point at their binary nature. We have examined various
elemental abundance ratios of the program stars and confirmed the low-mass nature of their former AGB
companions. We have shown that the i-process models could successfully reproduce the observed abundance
pattern in HE 1327−2116. The analysis performed for HE 0457−1805, HE 0920−0506, and HE 1241−0337
based on the FRUITY parametric models confirmed that the surface chemical compositions of these three objects
are influenced by pollution from low-mass AGB companions. |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
American Astronomical Society |
en_US |
dc.relation.uri |
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. |
|
dc.relation.uri |
https://doi.org/10.3847/1538-4357/ac7aac |
|
dc.rights |
© 2022. The Author(s). |
|
dc.subject |
Chemical abundances |
en_US |
dc.subject |
Chemically peculiar stars |
en_US |
dc.subject |
Carbon stars |
en_US |
dc.title |
Spectroscopic Study of Four Metal-poor Carbon Stars from the Hamburg/ESO Survey: On Confirming the Low-mass Nature of Their Companions* |
en_US |
dc.type |
Article |
en_US |