dc.contributor.author |
Susmitha, A |
|
dc.contributor.author |
Ojha, D. K |
|
dc.contributor.author |
Sivarani, T |
|
dc.contributor.author |
Ninan, J. P |
|
dc.contributor.author |
Bandyopadhyay, A |
|
dc.contributor.author |
Surya, Arun |
|
dc.contributor.author |
Unni, Athira |
|
dc.date.accessioned |
2021-09-13T06:33:52Z |
|
dc.date.available |
2021-09-13T06:33:52Z |
|
dc.date.issued |
2021-09 |
|
dc.identifier.citation |
Monthly notices of the Royal Astronomical Society, Vol. 506, No. 2, pp. 1962–1977 |
en_US |
dc.identifier.issn |
1365-2966 |
|
dc.identifier.uri |
http://hdl.handle.net/2248/7847 |
|
dc.description |
Restricted Access |
en_US |
dc.description.abstract |
We present the abundance analyses of seven carbon enhanced metal-poor (CEMP) stars to understand the origin of carbon in them. We used high-resolution optical spectra to derive abundances of various elements. We also used low-resolution near-infrared (NIR) spectra to derive the abundance of O and 12C/13C from the CO molecular band and compared their values with those derived from high-resolution optical spectra. We identified a good agreement between the values. Thus, in cool CEMP stars, the NIR observations complement the high-resolution optical observations to derive the oxygen abundance and the 12C/13C ratio. This enables us to probe fainter cool CEMP stars using NIR spectroscopy. C, N, O abundances of all the program stars in this study show abundances that are consistent with binary mass transfer from a low-mass, low-metallicity asymptotic giant branch (AGB) companion which is further supported by the presence of enhancement in neutron-capture elements and detection of radial velocity variation. One of the stars shows abundance patterns similar to a CEMP-s star whereas the abundance pattern of the rest of the stars satisfy the criteria required to classify them as CEMP-r/s stars. The subclassification of some of the stars studied here is revisited. The abundance of neutron-capture elements in these CEMP-r/s stars resembles to that of i-process models where proton ingestion episodes in the companion low-mass, low-metallicity AGB stars produce the necessary neutron density required for the onset of i-process. |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
Oxford University Press on behalf of Royal Astronomical Society |
en_US |
dc.relation.uri |
https://doi.org/10.1093/mnras/stab1508 |
|
dc.rights |
© The Royal Astronomical Society |
|
dc.subject |
Stars: abundances |
en_US |
dc.subject |
Stars: carbon |
en_US |
dc.subject |
Stars: low-mass |
en_US |
dc.subject |
Stars: low-mass |
en_US |
dc.subject |
Stars: Population II |
en_US |
dc.subject |
Galaxy: halo |
en_US |
dc.title |
Optical and NIR spectroscopy of cool CEMP stars to probe the nucleosynthesis in low-mass AGB binary system |
en_US |
dc.type |
Article |
en_US |