{
  "id": "2009.09003",
  "version": "v1",
  "published": "2020-09-18T18:22:06.000Z",
  "updated": "2020-09-18T18:22:06.000Z",
  "title": "Carbon, isotopic ratio $^{12}$C/$^{13}$C and nitrogen in solar twins: constraints for the chemical evolution of the local disc",
  "authors": [
    "Rafael Botelho",
    "Andre Milone",
    "Jorge Melendez",
    "Alan Alves-Brito",
    "Lorenzo Spina",
    "Jacob Beans"
  ],
  "comment": "Accepted for publication in MNRAS. The paper covers 20 pages, having 8 figures and 10 tables",
  "categories": [
    "astro-ph.SR",
    "astro-ph.EP",
    "astro-ph.GA"
  ],
  "abstract": "Abundances of light elements in dwarf stars of different ages are important constraints for stellar yields, Galactic chemical evolution and exoplanet chemical composition studies. We have measured C and N abundances and $^{12}$C/$^{13}$C ratios for a sample of 63 solar twins spanning a wide range in age, based on spectral synthesis of a comprehensive list of CH\\,A-X and CN\\,B-X features using HARPS spectra. The analysis of 55 thin disc solar twins confirms the dependences of [C/Fe] and [N/Fe] on [Fe/H]. [N/Fe] is investigated as a function of [Fe/H] and age for the first time for these stars. Our derived correlation [C/Fe]-age agrees with works for solar-type stars and solar twins, but the [N/Fe]-age correlation does not. The relations [C,N/Fe]-[Fe/H] and [C,N/Fe]-age for the solar twins lay under-solar. $^{12}$C/$^{13}$C is found correlated with [Fe/H] and seems to have decreased along the evolution of the local thin disc. Predictions from chemical evolution models for the solar vicinity corroborate the relations [C,N/Fe]-[Fe/H], $^{12}$C/$^{13}$C-age and [N/O]-[O/H], but do not for the $^{12}$C/$^{13}$C-[Fe/H] and [C/O]-[O/H] relations. The N/O ratio in the Sun is placed at the high end of the homogeneous distribution of solar twins, which suggests uniformity in the N-O budget for the formation of icy planetesimals, watery super-earths and giant planets. C and N had different nucleosynthetic origins along the thin disc evolution, as shown by the relations of [C/N], [C/O] and [N/O] against [O/H] and age. [C/N] and [C/O] are particularly observed increasing in time for solar twins younger than the Sun.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-09-18T18:22:06.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "chemical evolution",
      "local disc",
      "isotopic ratio",
      "constraints",
      "thin disc solar twins confirms"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 20,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}