{
  "id": "2312.02782",
  "version": "v1",
  "published": "2023-12-05T14:13:10.000Z",
  "updated": "2023-12-05T14:13:10.000Z",
  "title": "HI content at cosmic noon -- a millimeter-wavelength perspective",
  "authors": [
    "Hugo Messias",
    "Andrea Guerrero",
    "Neil Nagar",
    "Jack Regueiro",
    "Violette Impellizzeri",
    "Gustavo Orellana",
    "Miguel Vioque"
  ],
  "comment": "Submitted to MNRAS. Comments are welcomed",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "In other to understand galaxy growth evolution, it is critical to constrain the evolution of its building block: gas. Mostly comprised by Hydrogen in its neutral (HI) and molecular (H$_2$) phases, the latter is the one mostly directly associated to star-formation, while the neutral phase is considered the long-term gas reservoir. In this work, we make use of an empirical relation between dust emission at millimeter wavelengths and total gas mass in the inter-stellar medium (MHI plus MH2) in order to retrieve the HI content in galaxies. We assemble an heterogeneous sample of 335 galaxies at $0.01<z<6.4$ detected in both mm-continuum and carbon monoxide (CO), with special focus on a blindly selected sample to retrieve HI cosmological content when the Universe was ~2-6Gyr old ($1<z<3$). We find no significant evolution with redshift of the $M_{\\rm HI}/M_{\\rm H_2}$ ratio, which is about 1-3 (depending on the relation used to estimate $M_{\\rm HI}$). This also shows that $M_{\\rm H_2}$-based gas depletion times are underestimated overall by a factor of 2-4. Compared to local Universe HI mass functions, we find that the number density of galaxies with $M_{\\rm HI} > 10^{10.5} {\\rm M}_\\odot$ significantly decreased since 8-12Gyr ago. The specific sample used for this analysis is associated to 20-50% of the total cosmic HI content as estimated via Damped Lyman-alpha Absorbers. In IR luminous galaxies, HI mass content decreases between $z\\sim 2.5$ and $z\\sim 1.5$, while H$_2$ seems to increase. We also show source detection expectations for SKA surveys.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-12-05T14:13:10.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "cosmic noon",
      "millimeter-wavelength perspective",
      "local universe hi mass functions",
      "understand galaxy growth evolution",
      "hi mass content decreases"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}