{
  "id": "2004.11175",
  "version": "v1",
  "published": "2020-04-23T14:10:35.000Z",
  "updated": "2020-04-23T14:10:35.000Z",
  "title": "Differences and similarities of stellar populations in LAEs and LBGs at $z\\sim$ 3.4 - 6.8",
  "authors": [
    "P. Arrabal Haro",
    "J. M. Rodríguez Espinosa",
    "C. Muñoz-Tuñón",
    "D. Sobral",
    "A. Lumbreras-Calle",
    "M. Boquien",
    "A. Hernán-Caballero",
    "L. Rodríguez-Muñoz",
    "B. Alcalde Pampliega"
  ],
  "comment": "Accepted for publication in MNRAS. 18 pages, 23 figures",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "The differences between the inherent stellar populations (SPs) of LAEs and LBGs are a key factor in understanding early galaxy formation and evolution. We have run a set of SP burst-like models for a sample of 1,558 sources at $3.4<z<6.8$ from the Survey for High-$z$ Absorption Red and Dead Sources (SHARDS) over the GOODS-N field. This work focuses on the differences between the three different observational subfamilies of our sample: LAE-LBGs, no-Ly$\\alpha$ LBGs and pure LAEs. Single and double SP synthetic spectra were used to model the SEDs, adopting a Bayesian information criterion to analyse under which situations a second SP is required. We find that the sources are well modelled using a single SP in $\\sim79\\%$ of the cases. The best models suggest that pure LAEs are typically young low mass galaxies ($t\\sim26^{+41}_{-25}$ Myr; $M_{\\mathrm{star}}\\sim5.6^{+12.0}_{-5.5}\\times10^{8}\\ M_{\\odot}$), undergoing one of their first bursts of star formation. On the other hand, no-Ly$\\alpha$ LBGs require older SPs ($t\\sim71\\pm12$ Myr), and they are substantially more massive ($M_{\\mathrm{star}}\\sim3.5\\pm1.1\\times10^{9}\\ M_{\\odot}$). LAE-LBGs appear as the subgroup that more frequently needs the addition of a second SP, representing an old and massive galaxy caught in a strong recent star-forming episode. The relative number of sources found from each subfamily at each $z$ supports an evolutionary scenario from pure LAEs and single SP LAE-LBGs to more massive LBGs. Stellar Mass Functions are also derived, finding an increase of $M^{*}$ with cosmic time and a possible steepening of the low mass slope from $z\\sim6$ to $z\\sim5$ with no significant change to $z\\sim4$. Additionally, we have derived the SFR-$M_{\\mathrm{star}}$ relation, finding a $\\mathrm{SFR}\\propto M_{\\mathrm{star}}^{\\beta}$ behaviour with negligible evolution from $z\\sim4$ to $z\\sim6$.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-04-23T14:10:35.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "stellar populations",
      "differences",
      "pure laes",
      "typically young low mass galaxies",
      "second sp"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 18,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}