{
  "id": "2001.04378",
  "version": "v1",
  "published": "2020-01-13T16:30:03.000Z",
  "updated": "2020-01-13T16:30:03.000Z",
  "title": "Evidence of Spectral Evolution on the white dwarf sample from the Gaia Mission",
  "authors": [
    "G. Ourique",
    "S. O. Kepler",
    "A. D. Romero",
    "T. S. Klippel",
    "D. Koester"
  ],
  "comment": "9 pages, 9 figures, accepted by MNRAS",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "Since the Gaia data release 2, several works were published describing a bifurcation in the observed white dwarf colour$-$magnitude diagram for $\\mbox{$G_{\\mathrm{BP}}$}-\\mbox{$G_{\\mathrm{RP}}$} > 0$. Some possible explanations in the literature include the existence of a double population with different initial mass function or two distinct populations, one formed by hydrogen$-$ and one formed by helium$-$envelope white dwarfs. We propose instead spectral evolution to explain the bifurcation. From a population synthesis approach, we find that the spectral evolution occurs for effective temperature below ${\\simeq}11\\,000\\,\\mathrm{K}$ and masses mainly between $0.64\\,\\mathrm{M}_\\odot$ and $0.74\\,\\mathrm{M}_\\odot$, which correspond to around $16$ per cent of all DA white dwarfs. We also find the Gaia white dwarf colour-magnitude diagram indicates a star formation history that decreases abruptly for objects younger than $1.4\\,\\mathrm{Gyr}$ and a top-heavy initial mass function for the white dwarf progenitors.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-01-13T16:30:03.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "spectral evolution",
      "white dwarf sample",
      "gaia mission",
      "gaia white dwarf colour-magnitude diagram",
      "top-heavy initial mass function"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 9,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}