| Full text | |
| Author(s): Show less - |
Almeida-Fernandes, F.
;
Placco, V. M.
;
Rocha-Pinto, H. J.
;
Fernandes, M. B.
;
Limberg, G.
;
Silva, L. Beraldo E.
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Amarante, J. A. S.
;
Perottoni, H. D.
;
Overzier, R.
;
Schoenell, W.
;
Ribeiro, T.
;
Kanaan, A.
;
de Oliveira, C. Mendes
Total Authors: 13
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| Document type: | Journal article |
| Source: | Monthly Notices of the Royal Astronomical Society; v. 523, n. 2, p. 18-pg., 2023-05-30. |
| Abstract | |
Metal-poor stars are key to our understanding of the early stages of chemical evolution in the Universe. New multifilter surveys, such as the Southern Photometric Local Universe Survey (S-PLUS), are greatly advancing our ability to select low-metallicity stars. In this work, we analyse the chemodynamical properties and ages of 522 metal-poor candidates selected from the S-PLUS data release 3. About 92 per cent of these stars were confirmed to be metal-poor ([Fe/H] & LE; -1) based on previous medium-resolution spectroscopy. We calculated the dynamical properties of a subsample containing 241 stars, using the astrometry from Gaia Data Release 3. Stellar ages are estimated by a Bayesian isochronal method formalized in this work. We analyse the metallicity distribution of these metal-poor candidates separated into different subgroups of total velocity, dynamical properties, and ages. Our results are used to propose further restrictions to optimize the selection of metal-poor candidates in S-PLUS. The proposed astrometric selection (parallax >0.85 mas) is the one that returns the highest fraction of extremely metal-poor stars (16.3 per cent have [Fe/H] & LE; -3); the combined selection provides the highest fraction of very metal-poor stars (91.0 per cent have [Fe/H] & LE; -2), whereas the dynamical selection (eccentricity >0.35 and discness < 0.75) is better for targeting metal-poor (99.5 per cent have [Fe/H] & LE; -1). Using only S-PLUS photometric selections, it is possible to achieve selection fractions of 15.6, 88.5, and 98.3 per cent for metallicities below -3, -2, and -1, respectively. We also show that it is possible to use S-PLUS to target metal-poor stars in halo substructures such as Gaia-Sausage/Enceladus, Sequoia, Thamnos, and the Helmi stream. (AU) | |
| FAPESP's process: | 22/04079-0 - Characterizing ultra-faint dwarf galaxies with S-PLUS survey |
| Grantee: | Hélio Dotto Perottoni |
| Support Opportunities: | Scholarships abroad - Research Internship - Post-doctor |
| FAPESP's process: | 18/21250-9 - Identification of bright ultra-metal-poor stars from Multi-Band photometry and spectroscopic follow-up |
| Grantee: | Hélio Dotto Perottoni |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 21/10429-0 - The chemodynamical structure of the ancient galactic halo |
| Grantee: | Guilherme Limberg |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 22/07301-5 - Chemical-abundance patterns of disrupted dwarf galaxies |
| Grantee: | Guilherme Limberg |
| Support Opportunities: | Scholarships abroad - Research Internship - Doctorate (Direct) |
| FAPESP's process: | 21/09468-1 - Study of stellar populations in the S-PLUS survey |
| Grantee: | Felipe de Almeida Fernandes |
| Support Opportunities: | Scholarships abroad - Research Internship - Post-doctor |
| FAPESP's process: | 18/20977-2 - Identification of giant stars for mapping our Galaxy in the S-PLUS survey |
| Grantee: | Felipe de Almeida Fernandes |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |