دورية أكاديمية
The Pristine survey - XX: GTC follow-up observations of extremely metal-poor stars identified from Pristine and LAMOST
| العنوان: | The Pristine survey - XX: GTC follow-up observations of extremely metal-poor stars identified from Pristine and LAMOST |
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| المؤلفون: | Arentsen, Anke, Aguado, David S., Sestito, Federico, Hernández, González Jonay I., Martin, Nicolas F., Starkenburg, Else, Jablonka, Pascale, Yuan, Zhen |
| المساهمون: | Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), ANR-18-CE31-0017,Pristine,Pristine — Sondage des premières étoiles Galactiques(2018) |
| المصدر: | ISSN: 0035-8711. |
| بيانات النشر: | HAL CCSD Oxford University Press (OUP): Policy P - Oxford Open Option A |
| سنة النشر: | 2023 |
| المجموعة: | Archive de l'Observatoire de Paris (HAL) |
| مصطلحات موضوعية: | stars: Population II, Galaxy: halo, stars: chemically peculiar, techniques: spectroscopic, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics] |
| الوصف: | International audience ; Ultra metal-poor stars ($\rm {[Fe/H]} < -4.0$) are very rare, and finding them is a challenging task. Both narrow-band photometry and low-resolution spectroscopy have been useful tools for identifying candidates, and in this work we combine both approaches. We cross-matched metallicity-sensitive photometry from the Pristine survey with the low-resolution spectroscopic LAMOST database, and re-analysed all LAMOST spectra with $\rm {[Fe/H]} _{\it Pristine} <-2.5$. We find that ~1/3rd of this sample (selected without $\rm {[Fe/H]} _{\it Pristine}$ quality cuts) also have spectroscopic $\rm {[Fe/H]} < -2.5$. From this sample, containing many low signal-to-noise (S/N) spectra, we selected eleven stars potentially having $\rm {[Fe/H]} < -4.0$ or $\rm {[Fe/H]} < -3.0$ with very high carbon abundances, and we performed higher S/N medium-resolution spectroscopic follow-up with OSIRIS on the 10.4m Gran Telescopio Canarias (GTC). We confirm their extremely low metallicities, with a mean of $\rm {[Fe/H]} = -3.4$ and the most metal-poor star having $\rm {[Fe/H]} = -3.8$. Three of these are clearly carbon-enhanced metal-poor (CEMP) stars with $+1.65 < \rm {[C/Fe]} < +2.45$. The two most carbon-rich stars are either among the most metal-poor CEMP-s stars or the most carbon-rich CEMP-no stars known, the third is likely a CEMP-no star. We derived orbital properties for the OSIRIS sample and find that only one of our targets can be confidently associated with known substructures/accretion events, and that three out of four inner halo stars have prograde orbits. Large spectroscopic surveys may contain many hidden extremely and ultra metal-poor stars, and adding additional information from e.g. photometry as in this work can uncover them more efficiently and confidently. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| العلاقة: | info:eu-repo/semantics/altIdentifier/arxiv/2301.02265; insu-03952792; https://insu.hal.science/insu-03952792Test; https://insu.hal.science/insu-03952792/documentTest; https://insu.hal.science/insu-03952792/file/stad043.pdfTest; ARXIV: 2301.02265; BIBCODE: 2023MNRAS.tmp.58A |
| DOI: | 10.1093/mnras/stad043 |
| الإتاحة: | https://doi.org/10.1093/mnras/stad043Test https://insu.hal.science/insu-03952792Test https://insu.hal.science/insu-03952792/documentTest https://insu.hal.science/insu-03952792/file/stad043.pdfTest |
| حقوق: | info:eu-repo/semantics/OpenAccess |
| رقم الانضمام: | edsbas.E7A10F48 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1093/mnras/stad043 |
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